+Engineering Explained Hi Jason,big fan of your Channel and subscriber too.. Can you cover motorcycle engines and the advantages /disadvantage of high specific output high rpm engines. Scott.
+TheGray Aviator Absolutely! Lots of effort put in by the guy! I also like Chris Fix for his slightly offbeat but super practical and honest car fixes and tips. Do check it out!
I drive a 96 Buick Roadmaster. It's very heavy. I put drilled and slotted rotors on the front. Since then I've noticed that I can stop a lot faster. They might not be the best for racing, and might wear the pads faster, but for my heavy car and lead foot, I love them
I have to comment, I have a Porsche 997 Carrera that I track, I am a DE instructor with many years experience. My car came with drilled rotors and I added track pads, car stopped very well. Unfortunately as you stated the rotors eventually cracked between the holes. I switched to slotted rotors and immediately noticed a reduction in braking force. After many sets I went back to drilled rotors and the braking is much better. Just a personal observation, Porsche knows why the holes are there, it's not just looks.
My understanding of the reasoning behind drilled rotors is that it helps with initial pad bite, probably why Porsche installed them from the factory. I had a similar experience to you installing a drilled set on my 350z, noticeable improvement. I probably wouldn’t track the car with a drilled set given the risk of cracking, but it definitely helped improve braking on the street.
There is a reason why they are not used for racing because under extreme loads and longer periods of heavy use they can crack, for 20 minute sessions on the track however they are just fine. Cross drill rotors are just marginally better than blank rotors so it is true that they are mainly just for looks.
I run drilled and slotted on 98 expedition. started pulling a 6x12 open trailer with a riding lawn mower occasionally and immediately noticed that the truck didn't stop well with the extra weight. Purchased the drilled and slotted rotors and it's a world of difference. by the way if anyone is wondering about how I drive, I am a 23 year veteran truck driver with no accidents . All I'm saying is when I know what works for me, it's kind of hard for me to take advice from anyone who says otherwise.
On my minivans I switched to drilled and slotted discs as a method of cooling the disks faster. The stock discs were continually warping because of the long steep hills near my home. Switching has proven to be very effective as my discs have not warped for years since the switch. I go through pads more frequently but they are cheaper and easy to replace.
I know it’s 7 years later I’m commenting but I have a similar situation. Go up and down hills every time I leave my house. So have to ride the brakes often which has led to frequent rotor failure.
After watching videos for a while, I find your teaching method superb: You have the board you read off of which sums up what you're saying, but then elaborate off of that much more vocally, which is super useful for getting the gist and more.
-TwinTurbo250 Productions- Flutter isn't a valve. Its compressor surge. Basically if you have no blow off valve and your running all that air then slam the throttle shut its the sound of the air being forced back through the turbo. A lot of folks say its bad on the turbo, some say not so bad. Either way I would recommend a blow off valve to vent the excess pressure.
I'm not an engineer and I've heard both sides of the argument from engineers in the automotive industry. I chose the bov direction. You can choose the path you like.
He has no practical knowledge....its all from books. I bet he has never left hus house. Ask him what kind of car he drives and if he is an automotive engineer who has a job in the field or if he has any knowledge of cars outside of wiki pages
Thanks for the video, after watching this the first time I was in a mild fender bender in my SVT Focus in the rain. I had been driving for awhile without using my brakes when all of a sudden traffic stopped and I mashed the pedal to the floor, my car braked very slowly with no skidding or anti-lock and tapped the rear bumper of a Prius. After the accident I tested my brakes in the rain and realized that the first strong application was slow to stop but the next two got better and my anti-locks kicked in. My feeling was that the layer of water between the discs and pads hindered my initial braking effort. I remembered your video and avoided buying the drilled and slotted rotors and instead ordered EBC slotted rotors knowing that the pads might wear out faster but the extra biting edge and hopefully some water evacuation would be an improvement, thanks for steering me away from the drilled weaker rotors and keep up on the good informative videos!
What you mean to say is "fixed," with pistons on both sides of the caliper, as opposed to the more common "floating" or "sliding" caliper with pistons on only one side.
Brembo is a brand, not a style. All disc brakes (as far as I'm aware) range from a single piston, or "pot", through to 8 pistons ( I haven't heard of anything higher than 8 although I stand to be corrected).
There are functional advantages to using drilled rotors. Why this is so is a little complicated, and takes a few paragraphs to explain. (see below). That there are advantages is well established, and this is mostly their ability to bring a high performance pad up to peak temperature very rapidly. This is useful on lighter weight, performance oriented street cars and some forms of racing where the brake loads are intermittent. Drilled rotors are used on the street versions of high-performance cars which will never see any serious track time, but which may be driven quite vigorously from time to time. Sprint car racers also prefer them. All of this general group of performance cars driven mostly on the street [e.g. Lotus Elise, or Porsche Cayman] have brake pads with friction coefficients that increase as temperatures go up. These pads need to be warm to have the optimum response, and improved feel, during braking. Brake pads do not conduct heat well. Some have copper threads added to improve conduction, but basically a pad does not conduct much heat. The primary path for heat conduction out of the pad, is into the rotor. When a rotor is drilled or slotted the area for heat transfer out of the pad is reduced, and so the pad rises to 'operating temperature' much more quickly the same pad will come to temperature with a plain surfaced rotor. For a car equipped with higher temperature pads that is not driven on a circuit track, drilling or slotting the disk, reduces heat transfer out of the pads, bringing the brakes into their optimum working temperature immediately, the first time they are applied. There is no need for this rapid warm up on a car driven on a long circuit track, where the brakes are brought to temperature in the first turn and remain hot throughout the race. There are forms of racing in which drilled rotors are very much preferred. Drag racing is an obvious application. In this form of racing the brake pad must be brought to temperature very quickly and their brake disks are perforated to the point of looking like lace. Lighter weight open wheel cars like Sprint racers prefer drilled and/or perforated rotors, because braking loads are moderate, and the cooling of the disk itself is very rapid. Many 'sport' motor cycles use drilled rotors for this reason as well. These are all applications where drilled rotors are used for functional reasons. Drilled rotors, unlike slotted rotors, pump air through the holes as the leading edge of the brake pad approaches the hole. In a centrally vented rotor, the vanes in the center vent draw air from the holes and sling it outward in a continuous cooling loop. So drilled and perforated rotors have the advantage that while the pad heats more quickly, and the rotors themselves, having less mass may also spike in temperature, they also lose that heat very rapidly. For intermittent braking this is an advantage. For circuit racing drilled and slotted disks are generally a disadvantage. For rally cars, slotted are often preferred. Pad wear is greater, but so the braking, and that is to be expected. While the adhesives in brake pads no longer off-gas as badly as they once did, this is not the only source of gas between the pad and the rotor. Steam can be a serious problem in the initial applications of wet disk brakes. While driving in rain, drilled rotors provide an exit path for steam in a way other rotors do not. So there are all sorts of applications in which perforated rotors excel. And these applications have nothing to do with appearance. The limitation for drilled rotors is the potential for cracking. Cracking around the outermost holes can occur either when the rotor is used above its temperature range or when the quality of the casting is poor. There is no down side to using a drilled rotor in applications in which the heavy loads are intermittent, and there are many advantages, especially for lower power and lighter weight performance oriented cars.
+Diego Jimenez Getting the water and steam out is a really good idea on an exposed brake and cross drilling helps there. So do vertical slots in the brake pad. Both help. Drilling simply does not remove much weight, so there are better ways to remove the unsprung weight of a brake and caliper. Using aluminum for the body of the caliper, in preference to cast iron removes a lot. So does using an aluminum hub and a cast iron disk, as is commonly done with the Wilwood series of brakes. So cross drilling for weight reduction is not a strong motivation unless the brake disk is truly reduced to 'lace' as you will find on dragsters. Cross drilling is useful in a very specific niche of application. Consider the following: I drive a Miata in the mountains, and I will gain and lose a mile of altitude in a couple of hours. I work the brakes hard, but not as hard as a racer would because I am on public roads. My disks will go up to 1000F. I know this because I have measured them with a radiometer. So the stock brake pads do not work for me. The stock pad overheats. And the glue or binder from the pad, melts or burns on to the disk. As is mentioned by others posting on this page, when this happens, it feels like the disk is warped. But when you go to turn the brake disk you discover the disk is not warped at all; it just has a bit of a deposit in a few places from the brake getting fused onto the disk. So people like me with sporty vehicles driven hard, need a higher temperature pad, to survive the heat. But brake pads with higher temperature compounds, change their performance characteristics as they heat up. When they are cold they are 'okay' but when they are hot they are 'terrific'. Since people like me do not drive on a closed course, the pads do not heat up on the first turn, and remain hot for the rest of the drive. For our cars, which are driven hard but only on an intermittent basis, something needs to be done to cause the pads to come to temperature faster, and not over heat. Drilled disks reduce the heat transfer coefficient, by reducing the contact area, between pad and disk. So pads working on a drilled rotor come to temperature faster. This can be measured. The disks also cool faster than a solid disk, between applications of the brake pedal, when they are hot. So the temperature of a drilled rotor, and pad which rides on it, tends to spike faster and higher than a conventional disk. The disk also cools from that spike more quickly when the pressure is off the pad. I, and others, have measured this with radiometers. The measurement is an easy one with the right tool. And this is why you will find drilled rotors on Porsche Caymans, on Boxsters, on M Series BMWs, on AMG Mercedes, on the Lotus Elise and similar cars. This is not 'bling' or ornamentation. The engineers at these facilities know what they are doing. These are cars which are driven primarily on the street, which have higher temperature pads. The pads need heat to function in their optimum zone. And the brake needs to be cooled from that heat sooner. A cross drilled disk does both. The temperature spikes fast during brake application, and the disk cools from that temperature more quickly. Racing is q completely different story. Circuit racers do not use drilled disks for the most part, except in some special applications. In Sprint Car racing, or with lighter weight, lower power, open wheel race cars these some times benefit from the use of drilled disks. Heavier, higher power cars driven on a track generally do not benefit from a drilled disk. A lot of people think that drilled rotors are decorative, or are of the past. In the right application cross drilled rotors have an important function. This, and not tradition, is why you will see them installed as factory equipment on sporty vehicles with 'hot brakes' which are not driven continuously on a closed track.
I had thought that drilled helped remove water as well, but this isn't true. I had an issue with a BMW some years ago where it would get water (rain) on the rotor and the brakes would take literally a second before they would grab. I thought if I replaced the plain rotors with drilled (non-slotted) it would fix the problem, but it didn't.
My Mercedes S500 came from the factory with drilled rotors on the fronts. It's definitely not a performance car but the engineers put them in for a reason.
@Darren Curry: You might have 'glazed' or otherwise contaminated pads. Drilled, slotted or plain rotors with clean pads should not take so long to grab. The time should be a small fraction of a second.
I have a 25 year old E36 Bimmer and now run Drilled Vented Slotted front discs and Drilled Slotted rear discs both with ATE Low dust pads. Effing amazing stopping power. I'm in Perth Australia and it is very seasonal rain wise. Simply little chance of warping or cracking due to splashing hot discs. I suffer almost no fade even after a 3 am fast run across the city. For me, matched to Bilstein Shocks and up-rated roll bars, polyurethane bushes and a very worked engine I adore my car. Oh and I'm 52... not a kid.
where I used to live in Hawaii, I aways had a problem with warped rotors on my Toyota Sienna van. when driving home I had a long downhill trip that would heat up my brakes and warp them over time. I switched my rotors to cross drilled/slotted and never had that problem again. the cross drilled really does help heat reduction. it's not for just show or visual effect.
It's pretty cool how I needed brake advice and immediately searched "engineering explained brake rotors" and this video popped up with the exact unbiased science behind it that I was looking for. Thanks!
i've been researching brakes for months trying to figure out what actually works and if you actually get the performance you pay for. This video helps so much! Once again, you're the only person that makes videos that are completely blunt and direct so we can all understand in laymans terms. *I am going to choose the slotted rotors simply because i change my brake pads yearly anyways, so i'm not concerned with premature pad wear. But i DO want more brake bite. Thanks!
My personal favorite is vented/ slotted. On my heavy haul truck, it makes a huge difference over hilly braking conditions, upwards of a 200* reduction in temperature depending on overall duration and loading. Dropping from 650-700 down to about 500 taking some of my local hills. The slots aid in off road conditions... I have noticed a significant reduction in gouging since swapping out.
I have studied mechanic and one thing that people disdain is the torque. It can make total difference, not only about warping but also you don't brake any part inside torquing so much.
Straight forward, educational, and most especially, thank you for not wasting my life with useless information or extended product promotion while explaining to me exactly what I wanted to know! There should be more quality people on TH-cam like you. My hat is off to you and your videos!
Wow! I had no idea that drilled rotors are not only not the best option but they are actually worse than the other options in high performance applications. I'm learning a truckload of new things with your channel, thank you! Subscription well earned!
I ran drilled rotors on my daily driver ages ago, and they started to develop fractures around the holes after a couple years, despite my being a fairly conservative driver. I think it's just the nature of the beast!
@Transitive Wisdom Yeah, his rotors are cracking on the street because they are cheap aftermarket stuff. OEM Porsche, BMW, etc. drilled rotors don't crack unless they are tracked HARD. If your car didn't come with drilled rotors, don't use them.
@@flute136 Sorry, I don't have any experience with Powerstop drilled rotors to say if they are OEM quality or not. BMW and Porsche OEM rotors are often by Zimmermann. If your car came with plain rotors I'd stay with plain, you are losing swept area with drilled or slotted.
In defense: Drilled rotors should have less problems handling rain and mud, since the holes give fluid on the rotor or pad somewhere to go without all running or caking up on the pad. Thanks for this video! It simply explains things that should be easy to understand but get lost in all the debate and rumor.
Not to mention that the method for drilling the rotor is the leading cause for premature failure... either way, slotted or drilled or drilled and slotted provide better braking for a car than rotor blanks, and I've done hours of testing to prove that...
I've had my cross-drilled AND slotted rotors on my car for 5 plus years and auto crossed with it, and they are holding up fine. No stress cracks. They do get hot fast but I attribute that to the fact that I don't have air ducts to help with cooling.
Great video explaining the difference between the rotors! Nice to see a video explaining that although a tech might look as if it's "high performance" it might actually be worse than OEM. Great video!
All my drilled/slotted rotors that ive used have always far exceeded my stock brakes. Daily driven aswell and no cracks or issues. And yes they did see track use every weekend. Stopping was improved, fade was non existent in street use anymore and the initial brake bite was much more noticable.
Drilled without slots will also groove your pad, lead to reduced swept area and premature pad wear. Some companies just dimple their rotors to prevent cracking, but this is pretty much for show as well. Cheers Mr. EE!
You’re explanations are amazing. You provide detail and make it so people who don’t know anything feel like they can do everything. Your examples are really relatable and helpful as well. Keep up the good work
Each time I watch one of his videos, the more I wonder how his brain still fits in his skull. This guy is amazingly knowledgable and an excellent teacher. Keep up the good work boss!
May be worth pointing out that the straight vanes of standard vented rotors still act as an air pump. So if you are going to put in a venting system, the more you can focus it toward the center of the disk, the better. The curved vanes make a more efficient pump, so they move more air, and cool faster. The down side is that they are directional and more expensive.
This is great video but fails to mention one important thing: the slots are also there to drain water off the rotors in wet conditions.Also regarding drilled rotors, many racing rotors do come drilled, just look up Brembo 2L9.9001AR where just the two rear brakes cost over $20K, they are professional brake systems yet the rotors are still drilled.
replacing rotors on my car soon and this really helped decide what to go for. dont always agree with 100% of what you say but the math is always cool and most of the time your right.
Thank you so much for your stuff ... couple months ago I should have died in a car accident (provided I was following at the "recommended distance" on the highway), I just ended up ruining my brakes and rotors ... along with my front bumper, passenger headlight assembly, and I think the water pump. Been driving around with a wobble anytime I hit my brakes above 45mph. Just now getting around to changing them. This video definitely was more helpful than any review I could have read.
Well, this guy just totally changed my Amazon shopping cart. Thanks guy! Now I have like, $50 more in my wallet and the mechanic won't think I'm a douche for putting slotted drilled rotors on my Ford Focus!
You are awesome, my friend... These videos are some of the most accurate and trustworthy information available, without any b.s. at all. I learn something new every time I see one. Keep up the good work, brother.
My experience with drilled and slotted rotors is totally opposite of this video. I have two 2008 Chevy Impalas and with the stock vented and solid rotors, the brakes would heat up very fast under heavy braking, even normal driving going down hills or slowing from highway speeds. They would fade and eventually start to shake as they warped, but once they were cool they would stop shaking. I switch both cars to drilled and slotted rotors and all of those symptoms are 100% gone. The cars stop in shorter distances and I can brake MUCH more aggressively than with stock ones. I have yet to experience shaking or brake fade, even stopping the from 120mph to 0 mph. My brother has been running the same rotors and pads as mine on his 2003 Pontiac Grand Prix for 3 years and has had no issues with longevity, stress cracking or abnormal wearing.
Jayson Williams I installed drilled as slotted on my Lexus IS250 combined with Hawk ceramic pads and I could push the car real hard and breaking was 1000x better than with stock rotors and pads.
did you bother to replace your garbage oem brakes or you just threw one new brakes and thought it was good? I guarantee if you put a good street pad (hawk HPS 5.0) with some blank rotors, it would brake better than your current setup
You switched your pads too. That fade on the stock brakes and subsequent not fading with the aftermarket brakes is because you got better pads. Did you also flush your brake fluid? Because old fluid with particulates and water in it will boil well before fresh fluid would. Brake fade is simply your braking system unable to deal with the heat you are creating. Your rotors can play a role in reducing fade, but only if you go from solid to vented or upsize your rotors. I doubt you did either of those.
You stated that drilled rotors are not being used in F1 racing. True, but there is almost (perhaps not at all) no steel in them. Street cars are mostly steel, so there is no comparison between those two materials, considering heat resistance (thus, warping), heat transference capabilities and mechanical specs. There should be no comparison between apples and pears. Just my humble opinion, with all due respect.
dude, I love your vids and love that you are not crazy bias on your "experiments"...thanks for breaking things down quick and easy to all us simple people that know just enough to have a beginner conversation...lol keep it up!!!
THANK YOU for clarifying to the world that drilled rotors are simply cosmetic and that modern technology renders drilled rotors useless in the majority of applications. There are still many people out there that believe drilled rotors are the way to go, when for most applications involving hard use, it is not optimal.
When I bought my 2009 Accent SE, I installed drilled and slotted rotors and after 7 years and 50,000 miles I just replaced again, pads still probably had another 20,000 left but I just rather replace now than have the caliper piston at the end of its travel and for 91.00 pads on ebay included thought it was the right time. Old rotors didn't seem to have any stress cracks around the holes but some lines starting to appear.Probably saved 100.00 compared to a garageRemember also that most rotors are zinc coated so less prone to rust
Depends on the application. I use cross drilled and slotted on my Honda Odyssey because factory blanks would fade quickly because too much weight of the vehicle. The CD&S make the many van stop smoother and enable more aggressive driving. Not racing, just driving.
I've bought StopTech drilled rotors as an OEM replacement before and didn't have an issue with them at all. (And this is when i was 17 and thought I was a gt3 driver)... You will likely never make the rotor fail during daily use.
Sweet OTR plug. I'm a fan. nice exlaination. you probably then could talk about different compounds, types of metals but then it would take a hour and nobody would watch.
Sir that video was simple to the point and I actually got the information that I needed it prevented me from making a huge mistake and spending thousands on high end pretty breaks at this point I think I'll stick to plane vented breaks you earned a new subscriber 🖒
Good explanation and comparison. I would add that drilled rotors reduce rotational weight. Slotted rotors probably do also, but maybe not as much. I'm told a drilled rotor with chamfered holes does better as resisting cracking. Probably better on brake pad wear also.
pretty good description of rotors, slotted rotors are made to cut a fresh surface to the pads and keep them as flat as possible always giving a full pad surface for the most friction possible. the draw back is after the pads are done so are the rotors and they also have some vibrations from the slots scraping the pads at slower speeds. pretty sure formula racers use carbon fiber rotors that are able to handle much higher temps and reduce weight.
I've been riding motorcycles since the early 1970's. the 'new' disc brakes that were introduced were blank plates. In dry conditions they were way better than the older drum brakes (they had some serious fade issues), but in the wet you would get a film of water between the pad and the disc, plus the material issues you mentioned, and when pressed harder to try and slow down, the water would be suddenly be evicted and the front wheel would lock up, 90% of the time causing a crash. The first drilled rotors were amazing, they squeezed the water out the way. The compromise of less surface area was amazing. It would be great for you to do a video about the current motorcycle disc technology including drilled wave rotors (esp for Motocross), car technology in this area is way behind the motorcycles, bikes' designs are way more advanced, owing to the increased power outputs, and unpredictability of brakes than on a car.
I looked up your video because I was looking to fit crossdrilled discs on my car. The reason was that the wet performance on the standard ones is terrible to the point that it's hard to stop the car! I live in the west of Scotland, which is a notoriously damp part of the world. I wasn't aware of the cracking issue, so I'll keep that in mind when I speak to the brake fitter.
Anddddd i just bought drilled and slotted rotors for my car. Oh well. Not like the car won't stop right lol
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Jimmy Neutron keep them drilled and slotted dude! I actually have just a little experience with overheated brakes that were smoking. stock-solid rotors, having 1,200lbs loading in a ford f150 and going down the steepest seattle hill will over heat the brakes, then ya gotta kick that e-brake at the bottom to slow down cause your main brake is toast and smoking hot. [front brakes are disc, rear brakes are drum but terrible at braking] stock-solid rotors, another experience is when I had 5 construction workers (including me and I weigh 200lbs) in my 93 mercury cougar ford 5.0. I was cruising 60 in a 35 because we were taking a 30 minute lunch. The sign lied about restaurants at the next right and we found nothing after 10 minutes speed driving. So zooming back to the main street, we found a gas station only half mile beyond the stupid sign, my brakes were smoking all the way back until we started working again. Still full brake functional, unlike my f150 that loses brake power and resides on e-brake.
Tyee Cambrón you keep telling this story but don't realize it was your crappy brake pads. Rub some ebc brake pads and high temp brake fluid...also learn how to drive downhill. Semi trucks will overheat their brakes if they stay on them all the way down a hill...
First person I've seen online who has properly explained drilled/slotted rotors! I still learned something though! I didn't know pads had advanced and that gasses emitted from them aren't so much of an issue anymore. I guess I better trade my drilled and slotted rotors for some slotted-only ones.
As a Parts Specialist, Stoptech slotted/vented rotors is all I run & recommend for cars that are going to be ran in light racing events like Auto-Cross. All the teams in Pirelli World Challenge use them also. I've seen other event goers that used drilled/vented only to have cracks appear. I agree here. They may look cool but drilled offers no advantage with today's performance pads.
***** Stoptech Slotted rotors with PFC Brake Pads is a very good street/performance combo. I run that setup on my 1990 Mustang GT with upgraded Booster and master cylinder. You can find PFC branded brake pads at both O'Reillys and Autozone if you want to source them locally. Stoptech Rotors you can find at just about all the online performance E-Tailers, like Summit and Late Model Resto, etc., etc.
Hatsoff, its just awesome. All your videos makes a sense. The presenting method is so simple and fantastic, one of my favourite channels in youtube. 👌👌👌
Trust what he's saying. Race cars know best. They had huge problems using drilled rotors in racing when they 1st came out; they were cracking and blowing apart after heavy racing use. Now they just use slotted and solid rotors in racing; with venting of course.
+Mark Brooks Thank you for bringing in knowledge and uninebriation. It's quite unbelievable what some individuals dare to write in the comments containing their accumulation of pure and professional knowledge of...nothing.
I believe you are 100% correct on all points. Imagine my dismay when my 2007 Corvette ZO6 had drilled and slotted front rotors. I guess GM didn’t get the memo, and wanted to impress potential customers.
AP Racing or Akebono are the high-end manufacturers and maybe Brembo. Cant go wrong with that lot if you have deep pockets. If not the dep pockets, EBC Brakes are an excellent substitute.
And Wilwood? Looking for a system for my Ram 1500. I want 15" rotors that are 1.5" wide with 8 piston calipers all around. Only problem is that Brembo makes ZERO kits, let alone THAT kit for my truck. And last I checked, Brembo was the only one to even OFFER 8-piston calipers.
Thanks for clearing this up, Jason. Until now i was always under the impression that the drilled ones were better because high end cars tend to have them a lot of times.
i thought this guy had some qualification to do with engineering. Though i don't believe everything i'm told, i don't often have much reason to doubt this channel.
Love your videos. Brake rotors with holes do not create a fast temperature change. They cool off just about as fast as ones without the holes. I've seen temp tests measured on real street testing. But you are correct about surface being reduced with the many holes. I believe most all rotors are vented these days. And that is about the only thing that really matters. Temps do change higher and lower which is dependent more on racing and type of track. Not street use. For street use these do nothing to enhance the performance..or change temperature to benefits. Only the looks of them is the change. It is why you don't see spec temps listed for slotted or drilled rotors. The temp changes are really insignificant until you get to really racing around a track.
EE didn’t refer to a fast temperature change across the whole rotor. He specifically said holes result in rapid temperature ‘differential’ between areas of the rotor made of steel and adjacent areas made of well, air / nothing. Notably, the specific heat capacity of steel is 490 J/kg°C v. air at 1005 J/kg°C. That’s a significant differential that could lead to cracking even if only micro-cracks that only NDI can detect. Still, not good.
Thanks for the informative video! I'm in the middle of ripping out the front manual drum breaks on a '65 Mustang and was trying to figure out if it was worth investing in drilled and slotted disk rotors. Looks like I'll be spending a little more, but I kinda like the car so I suppose it's worth it.
Since I've been starting to mod my car, braking has been on my mind, and this video really helped me get an idea of what kind of brakes to upgrade to! Thanks!
Drilled rotors are commonly used in drifting because the brakes are hardly used so they don't see the drawbacks from other forms of racing but they reduce weight
I did put drilled and slotted rotors on the front of the 01 Ford Escape I owned years ago. I will say they stopped far faster in the rain. I only use ceramic pads now too.
Great concise review. Lots of good info. I have tried all 3. Believe the rotor & pad quality have a large impact on performance. OEM were plain vented, braking action not to my liking, when wet, slow response, needed lots of pressure.. The 1st were drilled & much better, instant stopping very strong power in all conditions. Next were drilled but warped quickly. 3rd set slotted. Best overall. Consistent strong linear response, long life.
IIRC high end "drilled" rotors are actually cast with the holes in them making them stronger compared to normal rotors that have holes drilled through them. And while they have less braking surface area and less thermal mass they do have more cooling surface area making them dissipate heat faster, correct me if I'm wrong.
AnotherSiGuy if you mean cast for cast irons, all other normal rotors is cast irons as well. From your words, less braking surface => less braking performance and less cooling surface. Less thermal mass => heat builds up faster. Meaning they have less heat capacity, and if you give them same stopping power, their temperature is higher. I purchased Stoptech drilled rotors when I started track driving, and I cracked both front side in 30min of first session. Drilled rotors are OK for street though, they are not for racing as EE said.
tbpom1003 My logic was that the inside of the holes would provide cooling surface area even though they do not provide braking surface area. Otherwise yes they would heat up faster and they won't brake as hard. Out of curiosity did you get the cryo-treated Stoptechs or the normal ones?
I just put slotted / vented / drilled front rotors on my 2012 Honda Odyssey which are prone to have warped rotors after a few thousand miles. Honda has a problem with their brake design and time will tell if this holds up but so far I'm happy with it.
***** It does happen regardless of types of brake rotors, expecially if the weather is cold, and you go through deep water. You only need to give some heat on your brake system, and water will evaporate in seconds.
***** correct, because no one drives with gt3 brakes in the rain on the highway. My regular rotors have done perfectly fine and has never done what you have experienced.
The Camaro ZL1 1LE has vented brakes and no drilling with only small slots. Its a track oriented car and probably near the top of the best cars in terms braking performance.
DGOfTheCentury Go ahead and order some slotted rust-proof center cap ones! Or upgrade to a slightly bigger brake kit without the cost of going Brembo! :D
DGOfTheCentury Just get plane rotors (they are all vented anyway nowadays), and just buy a can of high temp paint and paint the center it yourself. Personally I only order Brembo blanks, they are cheap.
Anywhere in this video does he mention that drilled rotors decrease unsprung weight? It bothers me when he says "there's no reason". There's always a reason when you build a race car or street car. Often, cost and application. This is the second video I've watched where incorrect conclusions or assumptions are made without asking all the questions about the application. The Ford GT, which is a purpose built race car for the street used drilled rotors (among many other supercars). I'm sure material removal, heat dissapation, unsprung weight all came into play and were measured. They didn't just drill into them "for some reason". They test everything. "Because they look cool", you call yourself engineering explained...that statement is a design statement or marketing and subjective.
Well, "because it looks cool" is not that strange. Very often looks are much more important than engineering. I know a guy that works in the aero department at Audi. He says the design guys always come first. If the aerodynamics don't "look cool" they're not going on the car, no matter how good they work. Ford isn't going to drill brake rotors to "remove material". If they needed to remove material, they'd just make them thinner. Unless of course, it looks cool and sells cars...
He's talking full blown race car applications don't run with drilled rotors because there's not enough of a benefit. He also mentioned that street cars/supercars use drilled rotors as part of aesthetics and that companies will make them strong enough for their main purpose, which is to stop a daily driven vehicle under normal driving conditions or a supercar that will be driven hard every once in a while, at best, unlike an actual race car that's driven hard for atleast 30-40 minutes to as many as 24 hours of hard driving.
Great vid'. I've had many "discussions" regarding drilled discs cracking where bogans insist they're soooo much better than slotted or non-drilled/slotted discs. The other disadvantage of drilled discs is that they don't sweep the entire disc, just the area of the holes. This leaves some gases in play.
Sometimes losing that mass can negatively affect the amount of heat the rotor can absorb too. Now ya have less metal, it gets hot faster with the same input. It's all tradeoffs
xsenceo89x or just making them smaller is option. also when smaller the diameter will be less so the top part of the disc will waste less kinetic energy because the top part of the disc is with higher speed than the car
Other things being equal, the only thing that matters in brakes is surface area. If you drill out metal, you reduce your surface area. This guy is honest and knows what he is talking about. Drilled discs are for people who don't think and don't understand engineering.
+mk ninin drag cars only need to use the brakes once, so drilled is fine because it's a way of removing weight. Also done in drifting where there isn't much braking. Nascar as well has minimal braking. There's enough air resistance that letting off is generally more than enough for speed adjustments.
I went to a Supertrofeo race back in 2013 and while walking through the pit garages during the race, one of the pit guys asked if I wanted a souvenir then handed me a carbon ceramic brake disk off one of the race cars. I don't know if they're 'drilled' but they do have holes in the braking surface just like a drilled rotor.. What's the story with these? They're glowing bright orange at the end of a straight. Do they just replace them so often it doesn't matter?
Carbon ceramic brakes are a different ball game when it comes to brake systems. Made from a different process, can hold higher heat, and last much longer. Hence their price tag.
+Faby0699 As mentioned above, CCB have much higher heat capacity and can handle deep heat cycling better than cast iron. They can also tolerate cracks better without compromising function or structural integrity.
yo bro I'm a fresh men in corona high I have auto and I saw your video on Monday night and on Tuesday morning In auto my auto shop teacher showed us drilled rotars I was the only one who knew why they where drilled, thank you for giving me some knowledge
Do you happen to know the difference between non abs rotors and abs rotors? i have a 240sx SE model with abs and having issues finding the correct info when looking for rotors.
I'll preface by stating i'm a Chief Engineer. You remind me of a lot of junior engineers just out of school. By that I mean you begin your sojourn in life believing you have a quick (albeit wrong) answer for everything. If you think AMG attaches drilled rotors to their products because it looks cool, I suggest you re-evaluate your "opinion". Engineers are essentially scientists and as such Engineers present facts to reinforce their hypothesis. RR C/E P/E
Just want to add that both the vented examples that were drawn act as air pumps, one relies on just centrifugal forces while the other uses a bend to assist and to possibly also increase surface area inside the vents.
Wow I always just assumed drilled was the best, just because everyone uses them on their high end cars. I guess I know why the P1 has those big plain vented rotors now.
I did put cross drilled rotors on my Prius. They work great.
6 ปีที่แล้ว +4
Now I love your channel....but this is a "SHOUTOUT".... to all americans....You can clearly see with your own eyes, that there is NO rotor.....IT IS A DISC!!!!! BREAK DISCS!!!!!......the rotor is the shaft. PS... Gotta say, thanks again for some great info & no nonsense opinion. best car info IMO.
Every plain surface rotor I had on my cars very quickly warped - usually before the first pad change. The drilled/slotted rotors have never warped on me - even after a couple of pad changes (didn't have a chance to check the performance beyond that as I got a new car which came stock with plain rotors).
+Bart Van Riel two piece sliding calipers are your standard everyday caliper that most cars have, they usually have one or two Pistons on one side, mono block fixed calipers a solid one piece with 4-6 Pistons with a 50/50 split have Pistons on both sides these brakes are much better because they are solid so no sliding parts which means less flex and normally have more Pistons pushing the pads, like AMGs Ferraris and Porsches have monoblock fixed calipers
Great video. If I might add, drilled rotors are also 'noisy' when the braking system of a given car, isn't engineered for their application. Slotted is always the way to go, in my opinion.
i have black diamond over size 308 mil drilled and grooved vented disks, they last years and give awsum braking performance. I have never had issues with cracks it all comes down to the quality of your disks more than anything.. but drilled works and combi like mine witch it grooved and drilled is simply awsum!!
I had cross drilled rotors for ten years without issues. Heat differential only becomes relevant in hard track racing. No street driven criss drilled rotor will ever get hot enough for it to be an issue. For street applications they are a huge improvement with zero chance of failure
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I put drilled-slotted-vented-carbon rotors on my Prius and now it stops so hard my wife's dentures fly out every time.
Damm, my wife hits me when i brake.
chazwazzum lmao
chazwazzum WHAT HELL? OLD PEOPLE SHOULDN’T DRIVE THAT FAST 😆😆😆
😭
@@sodapopkid12 who says he drive fast? it braking hard that cause it lol even some who brake from about 20mph can sometimes get you leave your seat
Man, your videos are simply fantastic! Such high quality content and they make perfect sense! Amongst the best channels on TH-cam!
+superhydrocarbon Thank you, I really appreciate it!
+Engineering Explained I wish I had your knowledge about vehicles. Never stop making videos!!
+Engineering Explained
Hi Jason,big fan of your Channel and subscriber too.. Can you cover motorcycle engines and the advantages /disadvantage of high specific output high rpm engines.
Scott.
+superhydrocarbon I totally agree with you. I've been learning quite a lot from his videos.
+TheGray Aviator Absolutely! Lots of effort put in by the guy! I also like Chris Fix for his slightly offbeat but super practical and honest car fixes and tips. Do check it out!
The drilled rotors not only look cool but according to ricers add 20 hp.
😂😂
+Mike Copper *аudible chuckle*
that's only if used in conjunction with red calipers. drilled by itself is only +10hp
+Bryan Parks those are cheap.. chinese versions.. get the one that has red caliper branded Rembo..you might get 30hp
No joke, I just bought slotted ebc rotors and yellow g2 caliper paint lol. But since mine are not drilled or red I'm only looking at a 5 hp increase.
I drive a 96 Buick Roadmaster. It's very heavy. I put drilled and slotted rotors on the front. Since then I've noticed that I can stop a lot faster. They might not be the best for racing, and might wear the pads faster, but for my heavy car and lead foot, I love them
I have to comment, I have a Porsche 997 Carrera that I track, I am a DE instructor with many years experience. My car came with drilled rotors and I added track pads, car stopped very well. Unfortunately as you stated the rotors eventually cracked between the holes. I switched to slotted rotors and immediately noticed a reduction in braking force. After many sets I went back to drilled rotors and the braking is much better. Just a personal observation, Porsche knows why the holes are there, it's not just looks.
Thanks for sharing your experience with it!
My understanding of the reasoning behind drilled rotors is that it helps with initial pad bite, probably why Porsche installed them from the factory. I had a similar experience to you installing a drilled set on my 350z, noticeable improvement. I probably wouldn’t track the car with a drilled set given the risk of cracking, but it definitely helped improve braking on the street.
@@natehess7663 This Uber driver will be taking your advice!
racekar80 the slotted ones were also high carbons as the originals are?
There is a reason why they are not used for racing because under extreme loads and longer periods of heavy use they can crack, for 20 minute sessions on the track however they are just fine. Cross drill rotors are just marginally better than blank rotors so it is true that they are mainly just for looks.
I run drilled and slotted on 98 expedition. started pulling a 6x12 open trailer with a riding lawn mower occasionally and immediately noticed that the truck didn't stop well with the extra weight. Purchased the drilled and slotted rotors and it's a world of difference. by the way if anyone is wondering about how I drive, I am a 23 year veteran truck driver with no accidents . All I'm saying is when I know what works for me, it's kind of hard for me to take advice from anyone who says otherwise.
On my minivans I switched to drilled and slotted discs as a method of cooling the disks faster. The stock discs were continually warping because of the long steep hills near my home. Switching has proven to be very effective as my discs have not warped for years since the switch. I go through pads more frequently but they are cheaper and easy to replace.
I know it’s 7 years later I’m commenting but I have a similar situation. Go up and down hills every time I leave my house. So have to ride the brakes often which has led to frequent rotor failure.
@@Paulog1990 Alternatively you could just drive in a lower gear when going downhill and not use the brakes as frequently.
@@rado2g I have a Nissan with a CVT. If you know anything about Nissan CVT’s, that’s the last thing I would try.
@@Paulog1990 not familiar with it, I drive a manual Audi A4 B8
@@Paulog1990😢😢😢
After watching videos for a while, I find your teaching method superb: You have the board you read off of which sums up what you're saying, but then elaborate off of that much more vocally, which is super useful for getting the gist and more.
PLEASE make a video about blowoff, diverter, flutter and all those kinds of Turbo Valves!
I think he already made a video about blow-offs. The turbo flutter or turbo surge i think is also mnetioned in the video.
-TwinTurbo250 Productions- Flutter isn't a valve. Its compressor surge. Basically if you have no blow off valve and your running all that air then slam the throttle shut its the sound of the air being forced back through the turbo. A lot of folks say its bad on the turbo, some say not so bad. Either way I would recommend a blow off valve to vent the excess pressure.
I'm not an engineer and I've heard both sides of the argument from engineers in the automotive industry. I chose the bov direction. You can choose the path you like.
He has no practical knowledge....its all from books. I bet he has never left hus house. Ask him what kind of car he drives and if he is an automotive engineer who has a job in the field or if he has any knowledge of cars outside of wiki pages
Mark Nope are you talking to me? I'm pretty sure he has decent practical knowledge as he builds race cars in his free time.
Thanks for the video, after watching this the first time I was in a mild fender bender in my SVT Focus in the rain. I had been driving for awhile without using my brakes when all of a sudden traffic stopped and I mashed the pedal to the floor, my car braked very slowly with no skidding or anti-lock and tapped the rear bumper of a Prius. After the accident I tested my brakes in the rain and realized that the first strong application was slow to stop but the next two got better and my anti-locks kicked in. My feeling was that the layer of water between the discs and pads hindered my initial braking effort.
I remembered your video and avoided buying the drilled and slotted rotors and instead ordered EBC slotted rotors knowing that the pads might wear out faster but the extra biting edge and hopefully some water evacuation would be an improvement, thanks for steering me away from the drilled weaker rotors and keep up on the good informative videos!
I'd be intersted in a video about "brembo style" brake calipers (4 pot, 6 pot, 8 pot...) compared to conventional style brake calipers
What you mean to say is "fixed," with pistons on both sides of the caliper, as opposed to the more common "floating" or "sliding" caliper with pistons on only one side.
but but but everyone on NASIOC knows that Brembo is better lmao
Brembo is a brand, not a style. All disc brakes (as far as I'm aware) range from a single piston, or "pot", through to 8 pistons ( I haven't heard of anything higher than 8 although I stand to be corrected).
Google "Tarox Brakes", you'll be surprised. ;-)
If you ever want to see an insane number of pistons on a caliper check out the Evolvo Volvo C30. That one runs 14 pistons.
There are functional advantages to using drilled rotors. Why this is so is a little complicated, and takes a few paragraphs to explain. (see below). That there are advantages is well established, and this is mostly their ability to bring a high performance pad up to peak temperature very rapidly. This is useful on lighter weight, performance oriented street cars and some forms of racing where the brake loads are intermittent.
Drilled rotors are used on the street versions of high-performance cars which will never see any serious track time, but which may be driven quite vigorously from time to time. Sprint car racers also prefer them. All of this general group of performance cars driven mostly on the street [e.g. Lotus Elise, or Porsche Cayman] have brake pads with friction coefficients that increase as temperatures go up. These pads need to be warm to have the optimum response, and improved feel, during braking.
Brake pads do not conduct heat well. Some have copper threads added to improve conduction, but basically a pad does not conduct much heat. The primary path for heat conduction out of the pad, is into the rotor. When a rotor is drilled or slotted the area for heat transfer out of the pad is reduced, and so the pad rises to 'operating temperature' much more quickly the same pad will come to temperature with a plain surfaced rotor.
For a car equipped with higher temperature pads that is not driven on a circuit track, drilling or slotting the disk, reduces heat transfer out of the pads, bringing the brakes into their optimum working temperature immediately, the first time they are applied. There is no need for this rapid warm up on a car driven on a long circuit track, where the brakes are brought to temperature in the first turn and remain hot throughout the race.
There are forms of racing in which drilled rotors are very much preferred. Drag racing is an obvious application. In this form of racing the brake pad must be brought to temperature very quickly and their brake disks are perforated to the point of looking like lace. Lighter weight open wheel cars like Sprint racers prefer drilled and/or perforated rotors, because braking loads are moderate, and the cooling of the disk itself is very rapid. Many 'sport' motor cycles use drilled rotors for this reason as well. These are all applications where drilled rotors are used for functional reasons.
Drilled rotors, unlike slotted rotors, pump air through the holes as the leading edge of the brake pad approaches the hole. In a centrally vented rotor, the vanes in the center vent draw air from the holes and sling it outward in a continuous cooling loop. So drilled and perforated rotors have the advantage that while the pad heats more quickly, and the rotors themselves, having less mass may also spike in temperature, they also lose that heat very rapidly. For intermittent braking this is an advantage. For circuit racing drilled and slotted disks are generally a disadvantage. For rally cars, slotted are often preferred. Pad wear is greater, but so the braking, and that is to be expected.
While the adhesives in brake pads no longer off-gas as badly as they once did, this is not the only source of gas between the pad and the rotor. Steam can be a serious problem in the initial applications of wet disk brakes. While driving in rain, drilled rotors provide an exit path for steam in a way other rotors do not. So there are all sorts of applications in which perforated rotors excel. And these applications have nothing to do with appearance. The limitation for drilled rotors is the potential for cracking. Cracking around the outermost holes can occur either when the rotor is used above its temperature range or when the quality of the casting is poor.
There is no down side to using a drilled rotor in applications in which the heavy loads are intermittent, and there are many advantages, especially for lower power and lighter weight performance oriented cars.
+maneki9neko I was under the impression that on motorcycles drilled rotors were primarily for 1 weight and 2 get all the mud, water crap out of there
+Diego Jimenez
Getting the water and steam out is a really good idea on an exposed brake and cross drilling helps there. So do vertical slots in the brake pad. Both help.
Drilling simply does not remove much weight, so there are better ways to remove the unsprung weight of a brake and caliper. Using aluminum for the body of the caliper, in preference to cast iron removes a lot. So does using an aluminum hub and a cast iron disk, as is commonly done with the Wilwood series of brakes. So cross drilling for weight reduction is not a strong motivation unless the brake disk is truly reduced to 'lace' as you will find on dragsters.
Cross drilling is useful in a very specific niche of application. Consider the following: I drive a Miata in the mountains, and I will gain and lose a mile of altitude in a couple of hours. I work the brakes hard, but not as hard as a racer would because I am on public roads. My disks will go up to 1000F. I know this because I have measured them with a radiometer. So the stock brake pads do not work for me. The stock pad overheats. And the glue or binder from the pad, melts or burns on to the disk.
As is mentioned by others posting on this page, when this happens, it feels like the disk is warped. But when you go to turn the brake disk you discover the disk is not warped at all; it just has a bit of a deposit in a few places from the brake getting fused onto the disk.
So people like me with sporty vehicles driven hard, need a higher temperature pad, to survive the heat. But brake pads with higher temperature compounds, change their performance characteristics as they heat up. When they are cold they are 'okay' but when they are hot they are 'terrific'. Since people like me do not drive on a closed course, the pads do not heat up on the first turn, and remain hot for the rest of the drive. For our cars, which are driven hard but only on an intermittent basis, something needs to be done to cause the pads to come to temperature faster, and not over heat.
Drilled disks reduce the heat transfer coefficient, by reducing the contact area, between pad and disk. So pads working on a drilled rotor come to temperature faster. This can be measured. The disks also cool faster than a solid disk, between applications of the brake pedal, when they are hot. So the temperature of a drilled rotor, and pad which rides on it, tends to spike faster and higher than a conventional disk. The disk also cools from that spike more quickly when the pressure is off the pad. I, and others, have measured this with radiometers. The measurement is an easy one with the right tool.
And this is why you will find drilled rotors on Porsche Caymans, on Boxsters, on M Series BMWs, on AMG Mercedes, on the Lotus Elise and similar cars. This is not 'bling' or ornamentation. The engineers at these facilities know what they are doing. These are cars which are driven primarily on the street, which have higher temperature pads. The pads need heat to function in their optimum zone. And the brake needs to be cooled from that heat sooner. A cross drilled disk does both. The temperature spikes fast during brake application, and the disk cools from that temperature more quickly.
Racing is q completely different story. Circuit racers do not use drilled disks for the most part, except in some special applications. In Sprint Car racing, or with lighter weight, lower power, open wheel race cars these some times benefit from the use of drilled disks. Heavier, higher power cars driven on a track generally do not benefit from a drilled disk.
A lot of people think that drilled rotors are decorative, or are of the past. In the right application cross drilled rotors have an important function. This, and not tradition, is why you will see them installed as factory equipment on sporty vehicles with 'hot brakes' which are not driven continuously on a closed track.
I had thought that drilled helped remove water as well, but this isn't true. I had an issue with a BMW some years ago where it would get water (rain) on the rotor and the brakes would take literally a second before they would grab. I thought if I replaced the plain rotors with drilled (non-slotted) it would fix the problem, but it didn't.
My Mercedes S500 came from the factory with drilled rotors on the fronts. It's definitely not a performance car but the engineers put them in for a reason.
@Darren Curry: You might have 'glazed' or otherwise contaminated pads. Drilled, slotted or plain rotors with clean pads should not take so long to grab. The time should be a small fraction of a second.
I have a 25 year old E36 Bimmer and now run Drilled Vented Slotted front discs and Drilled Slotted rear discs both with ATE Low dust pads. Effing amazing stopping power. I'm in Perth Australia and it is very seasonal rain wise. Simply little chance of warping or cracking due to splashing hot discs. I suffer almost no fade even after a 3 am fast run across the city.
For me, matched to Bilstein Shocks and up-rated roll bars, polyurethane bushes and a very worked engine I adore my car.
Oh and I'm 52... not a kid.
I'm 57, you're still a kid
Matt Caulfield I’m 63 and still a kid.. technically. I am beyond middle age. So I’m old. I still think I’m a kid though!
do you still have that bmw? it's been 5 years.
Nice, objective and un-sponsored truth.
oh good i recently buyed dba non drilled
Very informative video, please add me in Automobile Group, my WhatsApp number is +917405347520
👌
where I used to live in Hawaii, I aways had a problem with warped rotors on my Toyota Sienna van. when driving home I had a long downhill trip that would heat up my brakes and warp them over time. I switched my rotors to cross drilled/slotted and never had that problem again. the cross drilled really does help heat reduction. it's not for just show or visual effect.
It's pretty cool how I needed brake advice and immediately searched "engineering explained brake rotors" and this video popped up with the exact unbiased science behind it that I was looking for. Thanks!
i've been researching brakes for months trying to figure out what actually works and if you actually get the performance you pay for. This video helps so much! Once again, you're the only person that makes videos that are completely blunt and direct so we can all understand in laymans terms.
*I am going to choose the slotted rotors simply because i change my brake pads yearly anyways, so i'm not concerned with premature pad wear. But i DO want more brake bite. Thanks!
My personal favorite is vented/ slotted. On my heavy haul truck, it makes a huge difference over hilly braking conditions, upwards of a 200* reduction in temperature depending on overall duration and loading. Dropping from 650-700 down to about 500 taking some of my local hills. The slots aid in off road conditions... I have noticed a significant reduction in gouging since swapping out.
I was wondering about this. Thanks.
To everyone, remember this, TORQUE YOUR LUGNUTS, reduces warping.
Could be true. I've never heard this before but it couldn't hurt.
You were great against Gary Oldman. Too bad he snuck up on you at the end.
Thanks for the advice, I dealt with warped rotors in the past.
Sad that "car people" need to be told this. Even without the worry of rotorwarp, just keep your nuts tight, but not too tight!
I have studied mechanic and one thing that people disdain is the torque. It can make total difference, not only about warping but also you don't brake any part inside torquing so much.
Straight forward, educational, and most especially, thank you for not wasting my life with useless information or extended product promotion while explaining to me exactly what I wanted to know! There should be more quality people on TH-cam like you. My hat is off to you and your videos!
Wow! I had no idea that drilled rotors are not only not the best option but they are actually worse than the other options in high performance applications.
I'm learning a truckload of new things with your channel, thank you! Subscription well earned!
You save people so much time, you should be given the Nobel prize for automotive information delivery!!
I ran drilled rotors on my daily driver ages ago, and they started to develop fractures around the holes after a couple years, despite my being a fairly conservative driver. I think it's just the nature of the beast!
Your issue may stem from the fact you didn't change your rotors for 2+ years 💀
@Transitive Wisdom Yeah, his rotors are cracking on the street because they are cheap aftermarket stuff. OEM Porsche, BMW, etc. drilled rotors don't crack unless they are tracked HARD. If your car didn't come with drilled rotors, don't use them.
@@chrisbradley9607 what if i buy nice powerstop drilled and slotted rotors and my car came with plain rotors?
@@flute136 Sorry, I don't have any experience with Powerstop drilled rotors to say if they are OEM quality or not. BMW and Porsche OEM rotors are often by Zimmermann. If your car came with plain rotors I'd stay with plain, you are losing swept area with drilled or slotted.
@@chrisbradley9607 well theyre suppose to be an upgrade kit
In defense: Drilled rotors should have less problems handling rain and mud, since the holes give fluid on the rotor or pad somewhere to go without all running or caking up on the pad.
Thanks for this video! It simply explains things that should be easy to understand but get lost in all the debate and rumor.
Not to mention that the method for drilling the rotor is the leading cause for premature failure... either way, slotted or drilled or drilled and slotted provide better braking for a car than rotor blanks, and I've done hours of testing to prove that...
I've had my cross-drilled AND slotted rotors on my car for 5 plus years and auto crossed with it, and they are holding up fine. No stress cracks. They do get hot fast but I attribute that to the fact that I don't have air ducts to help with cooling.
I almost purchased drilled and slotted Akebonos and you just saved me a bunch of money. Thank you
Great video explaining the difference between the rotors! Nice to see a video explaining that although a tech might look as if it's "high performance" it might actually be worse than OEM. Great video!
I'm getting a big brake setup for Time attack, and you were the only one to actually say what the +/- are of each option 🙏🏿
Also u saved me money 😉
All my drilled/slotted rotors that ive used have always far exceeded my stock brakes. Daily driven aswell and no cracks or issues. And yes they did see track use every weekend. Stopping was improved, fade was non existent in street use anymore and the initial brake bite was much more noticable.
Drilled without slots will also groove your pad, lead to reduced swept area and premature pad wear. Some companies just dimple their rotors to prevent cracking, but this is pretty much for show as well. Cheers Mr. EE!
You’re explanations are amazing. You provide detail and make it so people who don’t know anything feel like they can do everything. Your examples are really relatable and helpful as well. Keep up the good work
I like how you use different colors on the whiteboard. It really helps understand the points you're making.
Each time I watch one of his videos, the more I wonder how his brain still fits in his skull.
This guy is amazingly knowledgable and an excellent teacher.
Keep up the good work boss!
years of aggressive engineering schooling will do that to a man
May be worth pointing out that the straight vanes of standard vented rotors still act as an air pump. So if you are going to put in a venting system, the more you can focus it toward the center of the disk, the better.
The curved vanes make a more efficient pump, so they move more air, and cool faster. The down side is that they are directional and more expensive.
Can you do one on the advantages and disadvantages of different brake pads (ie ceramic) and also of different brake types (disc, rotor and air)?
This is great video but fails to mention one important thing: the slots are also there to drain water off the rotors in wet conditions.Also regarding drilled rotors, many racing rotors do come drilled, just look up Brembo 2L9.9001AR where just the two rear brakes cost over $20K, they are professional brake systems yet the rotors are still drilled.
After watching this video I decided to buy cross drilled slotted rotors for my 2010 Pilot :D
Best overall channel for automotive maintenance and repair!
Thanks man, I braked for this video.
PapayaMan oh give me a brake...
Don't brake the chain
Brake time! (munches kit-kat)
did I make it or brake it in time?
Stop!!! these comments are killing me. :D
replacing rotors on my car soon and this really helped decide what to go for. dont always agree with 100% of what you say but the math is always cool and most of the time your right.
Love your videos. Crossdrilled rotors are often used for qualifying where a team will be replacing the rotors before the actual race.
Thank you so much for your stuff ... couple months ago I should have died in a car accident (provided I was following at the "recommended distance" on the highway), I just ended up ruining my brakes and rotors ... along with my front bumper, passenger headlight assembly, and I think the water pump. Been driving around with a wobble anytime I hit my brakes above 45mph. Just now getting around to changing them. This video definitely was more helpful than any review I could have read.
Well, this guy just totally changed my Amazon shopping cart. Thanks guy! Now I have like, $50 more in my wallet and the mechanic won't think I'm a douche for putting slotted drilled rotors on my Ford Focus!
You are awesome, my friend...
These videos are some of the most accurate and trustworthy information available, without any b.s. at all. I learn something new every time I see one. Keep up the good work, brother.
My experience with drilled and slotted rotors is totally opposite of this video. I have two 2008 Chevy Impalas and with the stock vented and solid rotors, the brakes would heat up very fast under heavy braking, even normal driving going down hills or slowing from highway speeds. They would fade and eventually start to shake as they warped, but once they were cool they would stop shaking. I switch both cars to drilled and slotted rotors and all of those symptoms are 100% gone. The cars stop in shorter distances and I can brake MUCH more aggressively than with stock ones. I have yet to experience shaking or brake fade, even stopping the from 120mph to 0 mph. My brother has been running the same rotors and pads as mine on his 2003 Pontiac Grand Prix for 3 years and has had no issues with longevity, stress cracking or abnormal wearing.
Jayson Williams I installed drilled as slotted on my Lexus IS250 combined with Hawk ceramic pads and I could push the car real hard and breaking was 1000x better than with stock rotors and pads.
That’s one of the things I changed on my 08 Impala. It stops a lot Better now that I put EBC slotted rotors on it.
Anyone got a link for some good ones for my 2014 Chevy malibu
did you bother to replace your garbage oem brakes or you just threw one new brakes and thought it was good? I guarantee if you put a good street pad (hawk HPS 5.0) with some blank rotors, it would brake better than your current setup
You switched your pads too. That fade on the stock brakes and subsequent not fading with the aftermarket brakes is because you got better pads.
Did you also flush your brake fluid? Because old fluid with particulates and water in it will boil well before fresh fluid would.
Brake fade is simply your braking system unable to deal with the heat you are creating. Your rotors can play a role in reducing fade, but only if you go from solid to vented or upsize your rotors. I doubt you did either of those.
I REALLY LIKE THIS KID ITS STRAIGHT FORWARD TO THE POINT, KEEP UP THE GOOD WORK KID.....displaced heat
You stated that drilled rotors are not being used in F1 racing. True, but there is almost (perhaps not at all) no steel in them. Street cars are mostly steel, so there is no comparison between those two materials, considering heat resistance (thus, warping), heat transference capabilities and mechanical specs. There should be no comparison between apples and pears. Just my humble opinion, with all due respect.
dude, I love your vids and love that you are not crazy bias on your "experiments"...thanks for breaking things down quick and easy to all us simple people that know just enough to have a beginner conversation...lol
keep it up!!!
Loved you in Napoleon dynamite!
THANK YOU for clarifying to the world that drilled rotors are simply cosmetic and that modern technology renders drilled rotors useless in the majority of applications. There are still many people out there that believe drilled rotors are the way to go, when for most applications involving hard use, it is not optimal.
When I bought my 2009 Accent SE, I installed drilled and slotted rotors and after 7 years and 50,000 miles I just replaced again, pads still probably had another 20,000 left but I just rather replace now than have the caliper piston at the end of its travel and for 91.00 pads on ebay included thought it was the right time. Old rotors didn't seem to have any stress cracks around the holes but some lines starting to appear.Probably saved 100.00 compared to a garageRemember also that most rotors are zinc coated so less prone to rust
Depends on the application. I use cross drilled and slotted on my Honda Odyssey because factory blanks would fade quickly because too much weight of the vehicle. The CD&S make the many van stop smoother and enable more aggressive driving. Not racing, just driving.
I've bought StopTech drilled rotors as an OEM replacement before and didn't have an issue with them at all. (And this is when i was 17 and thought I was a gt3 driver)... You will likely never make the rotor fail during daily use.
Sweet OTR plug. I'm a fan. nice exlaination. you probably then could talk about different compounds, types of metals but then it would take a hour and nobody would watch.
“Well because it looks awesome” quoted every single car guy right there 😂
Sir that video was simple to the point and I actually got the information that I needed it prevented me from making a huge mistake and spending thousands on high end pretty breaks at this point I think I'll stick to plane vented breaks you earned a new subscriber 🖒
Good explanation and comparison. I would add that drilled rotors reduce rotational weight. Slotted rotors probably do also, but maybe not as much. I'm told a drilled rotor with chamfered holes does better as resisting cracking. Probably better on brake pad wear also.
pretty good description of rotors, slotted rotors are made to cut a fresh surface to the pads and keep them as flat as possible always giving a full pad surface for the most friction possible. the draw back is after the pads are done so are the rotors and they also have some vibrations from the slots scraping the pads at slower speeds. pretty sure formula racers use carbon fiber rotors that are able to handle much higher temps and reduce weight.
I've been riding motorcycles since the early 1970's. the 'new' disc brakes that were introduced were blank plates. In dry conditions they were way better than the older drum brakes (they had some serious fade issues), but in the wet you would get a film of water between the pad and the disc, plus the material issues you mentioned, and when pressed harder to try and slow down, the water would be suddenly be evicted and the front wheel would lock up, 90% of the time causing a crash. The first drilled rotors were amazing, they squeezed the water out the way. The compromise of less surface area was amazing. It would be great for you to do a video about the current motorcycle disc technology including drilled wave rotors (esp for Motocross), car technology in this area is way behind the motorcycles, bikes' designs are way more advanced, owing to the increased power outputs, and unpredictability of brakes than on a car.
yes drilled wave rotors are prominent in mountain bike applications to keep rotational weight down. they never do solid or grooved.
I looked up your video because I was looking to fit crossdrilled discs on my car. The reason was that the wet performance on the standard ones is terrible to the point that it's hard to stop the car! I live in the west of Scotland, which is a notoriously damp part of the world. I wasn't aware of the cracking issue, so I'll keep that in mind when I speak to the brake fitter.
Anddddd i just bought drilled and slotted rotors for my car. Oh well. Not like the car won't stop right lol
Jimmy Neutron keep them drilled and slotted dude! I actually have just a little experience with overheated brakes that were smoking.
stock-solid rotors, having 1,200lbs loading in a ford f150 and going down the steepest seattle hill will over heat the brakes, then ya gotta kick that e-brake at the bottom to slow down cause your main brake is toast and smoking hot. [front brakes are disc, rear brakes are drum but terrible at braking]
stock-solid rotors, another experience is when I had 5 construction workers (including me and I weigh 200lbs) in my 93 mercury cougar ford 5.0.
I was cruising 60 in a 35 because we were taking a 30 minute lunch. The sign lied about restaurants at the next right and we found nothing after 10 minutes speed driving. So zooming back to the main street, we found a gas station only half mile beyond the stupid sign, my brakes were smoking all the way back until we started working again. Still full brake functional, unlike my f150 that loses brake power and resides on e-brake.
Tyee Cambrón you keep telling this story but don't realize it was your crappy brake pads. Rub some ebc brake pads and high temp brake fluid...also learn how to drive downhill. Semi trucks will overheat their brakes if they stay on them all the way down a hill...
+Jamais Vu (Symbolic) semi trucks don't use their brakes until they're going quite slow anyway. they're SUPER expensive to replace
My dad Drives trucks and they use them at all speeds. They just don't stay on it
+Jamais Vu (Symbolic) I totally agree with you, my dad is a truck driver also.
First person I've seen online who has properly explained drilled/slotted rotors!
I still learned something though! I didn't know pads had advanced and that gasses emitted from them aren't so much of an issue anymore. I guess I better trade my drilled and slotted rotors for some slotted-only ones.
+UndergroundTrev theres a good post on nasioc forums about this and other brake myths
As a Parts Specialist, Stoptech slotted/vented rotors is all I run & recommend for cars that are going to be ran in light racing events like Auto-Cross. All the teams in Pirelli World Challenge use them also. I've seen other event goers that used drilled/vented only to have cracks appear. I agree here. They may look cool but drilled offers no advantage with today's performance pads.
***** Stoptech Slotted rotors with PFC Brake Pads is a very good street/performance combo. I run that setup on my 1990 Mustang GT with upgraded Booster and master cylinder. You can find PFC branded brake pads at both O'Reillys and Autozone if you want to source them locally. Stoptech Rotors you can find at just about all the online performance E-Tailers, like Summit and Late Model Resto, etc., etc.
+thebayareapimp Slotted rotors? No. Drilled I've seen cracking long ago. not recently though. they're OK for street duty
+thebayareapimp Slotted rotors? No. Drilled I've seen cracking long ago. not recently though. they're OK for street duty
Hatsoff, its just awesome. All your videos makes a sense. The presenting method is so simple and fantastic, one of my favourite channels in youtube. 👌👌👌
I've had my Brembo Gran Turismo, 4-piston cross drilled rotors for over 7 years on my car. Not one crack yet, and I haven't had to replace my rotors.
Trust what he's saying. Race cars know best. They had huge problems using drilled rotors in racing when they 1st came out; they were cracking and blowing apart after heavy racing use. Now they just use slotted and solid rotors in racing; with venting of course.
+Mark Brooks Thank you for bringing in knowledge and uninebriation. It's quite unbelievable what some individuals dare to write in the comments containing their accumulation of pure and professional knowledge of...nothing.
+1czelaya 7 years? Maybe you don't drive often or hard, my rotors are shot in 4 years minimum.
I believe you are 100% correct on all points. Imagine my dismay when my 2007 Corvette ZO6 had drilled and slotted front rotors. I guess GM didn’t get the memo, and wanted to impress potential customers.
AP Racing or Akebono are the high-end manufacturers and maybe Brembo. Cant go wrong with that lot if you have deep pockets. If not the dep pockets, EBC Brakes are an excellent substitute.
And Wilwood?
Looking for a system for my Ram 1500. I want 15" rotors that are 1.5" wide with 8 piston calipers all around. Only problem is that Brembo makes ZERO kits, let alone THAT kit for my truck. And last I checked, Brembo was the only one to even OFFER 8-piston calipers.
Wilwood are fine too.
Thanks for clearing this up, Jason.
Until now i was always under the impression that the drilled ones were better because high end cars tend to have them a lot of times.
i thought this guy had some qualification to do with engineering. Though i don't believe everything i'm told, i don't often have much reason to doubt this channel.
"Because it looks awesome and well, it does look awesome!"
Love your videos. Brake rotors with holes do not create a fast temperature change. They cool off just about as fast as ones without the holes. I've seen temp tests measured on real street testing. But you are correct about surface being reduced with the many holes. I believe most all rotors are vented these days. And that is about the only thing that really matters. Temps do change higher and lower which is dependent more on racing and type of track. Not street use. For street use these do nothing to enhance the performance..or change temperature to benefits. Only the looks of them is the change. It is why you don't see spec temps listed for slotted or drilled rotors. The temp changes are really insignificant until you get to really racing around a track.
EE didn’t refer to a fast temperature change across the whole rotor. He specifically said holes result in rapid temperature ‘differential’ between areas of the rotor made of steel and adjacent areas made of well, air / nothing. Notably, the specific heat capacity of steel is 490 J/kg°C v. air at 1005 J/kg°C. That’s a significant differential that could lead to cracking even if only micro-cracks that only NDI can detect. Still, not good.
Thanks for the informative video! I'm in the middle of ripping out the front manual drum breaks on a '65 Mustang and was trying to figure out if it was worth investing in drilled and slotted disk rotors. Looks like I'll be spending a little more, but I kinda like the car so I suppose it's worth it.
Since I've been starting to mod my car, braking has been on my mind, and this video really helped me get an idea of what kind of brakes to upgrade to! Thanks!
Drilled rotors are commonly used in drifting because the brakes are hardly used so they don't see the drawbacks from other forms of racing but they reduce weight
Fred Mccue As mentioned in my Formula Drift video. :)
How much weight is really saved? Can that make a difference? I don't think so.
I did put drilled and slotted rotors on the front of the 01 Ford Escape I owned years ago. I will say they stopped far faster in the rain. I only use ceramic pads now too.
my civic has slotted vented drilled pads and painted red. plus ceramic pads. i beat ferraris and adds 50 hp each
Does it have v tak?
Just wait till you install a cold air intake. You'll have trouble keeping that wicked Civic on the ground.
Great concise review. Lots of good info. I have tried all 3. Believe the rotor & pad quality have a large impact on performance. OEM were plain vented, braking action not to my liking, when wet, slow response, needed lots of pressure.. The 1st were drilled & much better, instant stopping very strong power in all conditions. Next were drilled but warped quickly. 3rd set slotted. Best overall. Consistent strong linear response, long life.
IIRC high end "drilled" rotors are actually cast with the holes in them making them stronger compared to normal rotors that have holes drilled through them. And while they have less braking surface area and less thermal mass they do have more cooling surface area making them dissipate heat faster, correct me if I'm wrong.
AnotherSiGuy pls explain sempai Engineering Explained
Jad Makarem i just made a super long comment about experiences i had
Tyee Cambrón just read it, thanks man
AnotherSiGuy if you mean cast for cast irons, all other normal rotors is cast irons as well.
From your words, less braking surface => less braking performance and less cooling surface. Less thermal mass => heat builds up faster. Meaning they have less heat capacity, and if you give them same stopping power, their temperature is higher.
I purchased Stoptech drilled rotors when I started track driving, and I cracked both front side in 30min of first session.
Drilled rotors are OK for street though, they are not for racing as EE said.
tbpom1003 My logic was that the inside of the holes would provide cooling surface area even though they do not provide braking surface area. Otherwise yes they would heat up faster and they won't brake as hard. Out of curiosity did you get the cryo-treated Stoptechs or the normal ones?
I just put slotted / vented / drilled front rotors on my 2012 Honda Odyssey which are prone to have warped rotors after a few thousand miles. Honda has a problem with their brake design and time will tell if this holds up but so far I'm happy with it.
This cleared up a lot of controversy, thanks
TheCowGoesMoo o yes it does
***** It does happen regardless of types of brake rotors, expecially if the weather is cold, and you go through deep water.
You only need to give some heat on your brake system, and water will evaporate in seconds.
***** correct, because no one drives with gt3 brakes in the rain on the highway. My regular rotors have done perfectly fine and has never done what you have experienced.
Someone needs to make an educational video to tell people that brake rotors don't warp. I think you are the man to do it
So AMG and Ferrari sacrifice brake performance for "cool looks"?!! I don't think so.
Knowledge Sharing amg definitely lmao Ferrari maybe.
Agree, if Ferrari stopped putting drilled rotors on their cars, everyone else would follow. So, there must be a performance benefit.
James Carter not if they know they car isnt doing some serious track time, just compare they're production cars to actual track cars
No, buyers of AMG and Frerrari sacrifice a lot of money for "cool looks" and than stand in traffic next to priuses :)
The Camaro ZL1 1LE has vented brakes and no drilling with only small slots. Its a track oriented car and probably near the top of the best cars in terms braking performance.
The timing of this video is amazing...i was just about to order slotted and drilled rotors for my car, but i will just stick with my vented ones.
DGOfTheCentury Go ahead and order some slotted rust-proof center cap ones! Or upgrade to a slightly bigger brake kit without the cost of going Brembo! :D
DGOfTheCentury Just get plane rotors (they are all vented anyway nowadays), and just buy a can of high temp paint and paint the center it yourself. Personally I only order Brembo blanks, they are cheap.
DGOfTheCentury like was said above brembo blanks are the go to. They are reliable, and in-expensive.
Anywhere in this video does he mention that drilled rotors decrease unsprung weight? It bothers me when he says "there's no reason". There's always a reason when you build a race car or street car. Often, cost and application. This is the second video I've watched where incorrect conclusions or assumptions are made without asking all the questions about the application. The Ford GT, which is a purpose built race car for the street used drilled rotors (among many other supercars). I'm sure material removal, heat dissapation, unsprung weight all came into play and were measured. They didn't just drill into them "for some reason". They test everything. "Because they look cool", you call yourself engineering explained...that statement is a design statement or marketing and subjective.
Well, "because it looks cool" is not that strange. Very often looks are much more important than engineering.
I know a guy that works in the aero department at Audi. He says the design guys always come first. If the aerodynamics don't "look cool" they're not going on the car, no matter how good they work.
Ford isn't going to drill brake rotors to "remove material". If they needed to remove material, they'd just make them thinner. Unless of course, it looks cool and sells cars...
Yeah thats why racing teams have gotten away from drilled even the new c7's are vented two piece rotors
He's talking full blown race car applications don't run with drilled rotors because there's not enough of a benefit. He also mentioned that street cars/supercars use drilled rotors as part of aesthetics and that companies will make them strong enough for their main purpose, which is to stop a daily driven vehicle under normal driving conditions or a supercar that will be driven hard every once in a while, at best, unlike an actual race car that's driven hard for atleast 30-40 minutes to as many as 24 hours of hard driving.
Great vid'. I've had many "discussions" regarding drilled discs cracking where bogans insist they're soooo much better than slotted or non-drilled/slotted discs. The other disadvantage of drilled discs is that they don't sweep the entire disc, just the area of the holes. This leaves some gases in play.
I thought the drilled rotors were popular to save weight. Kind of like a lightened flywheel. Itll take less force to spin something that weighs less.
xsenceo89x How much weight?
Engineering Explained That un-sprung, rotational weight yo
Engineering Explained A couple of grams I'd guess 😂
Sometimes losing that mass can negatively affect the amount of heat the rotor can absorb too.
Now ya have less metal, it gets hot faster with the same input.
It's all tradeoffs
xsenceo89x or just making them smaller is option. also when smaller the diameter will be less so the top part of the disc will waste less kinetic energy because the top part of the disc is with higher speed than the car
Other things being equal, the only thing that matters in brakes is surface area. If you drill out metal, you reduce your surface area. This guy is honest and knows what he is talking about. Drilled discs are for people who don't think and don't understand engineering.
have you ever watched a race or worked on a pit crew I have and drag cars and nascar use drilled and sloted rotters
+mk ninin drag cars only need to use the brakes once, so drilled is fine because it's a way of removing weight. Also done in drifting where there isn't much braking. Nascar as well has minimal braking. There's enough air resistance that letting off is generally more than enough for speed adjustments.
I went to a Supertrofeo race back in 2013 and while walking through the pit garages during the race, one of the pit guys asked if I wanted a souvenir then handed me a carbon ceramic brake disk off one of the race cars. I don't know if they're 'drilled' but they do have holes in the braking surface just like a drilled rotor.. What's the story with these? They're glowing bright orange at the end of a straight. Do they just replace them so often it doesn't matter?
Carbon ceramic brakes are a different ball game when it comes to brake systems. Made from a different process, can hold higher heat, and last much longer. Hence their price tag.
how about formula one or motogp, they have disk brakes called 1200 holes made in carbo-ceramic compound, why are they using them if they might fail?
+Faby0699 As mentioned above, CCB have much higher heat capacity and can handle deep heat cycling better than cast iron. They can also tolerate cracks better without compromising function or structural integrity.
yo bro I'm a fresh men in corona high I have auto and I saw your video on Monday night and on Tuesday morning In auto my auto shop teacher showed us drilled rotars I was the only one who knew why they where drilled, thank you for giving me some knowledge
+sidewayz nation happy to hear it, thanks for watching!
Do you happen to know the difference between non abs rotors and abs rotors? i have a 240sx SE model with abs and having issues finding the correct info when looking for rotors.
I'll preface by stating i'm a Chief Engineer. You remind me of a lot of junior engineers just out of school. By that I mean you begin your sojourn in life believing you have a quick (albeit wrong) answer for everything. If you think AMG attaches drilled rotors to their products because it looks cool, I suggest you re-evaluate your "opinion". Engineers are essentially scientists and as such Engineers present facts to reinforce their hypothesis. RR C/E P/E
@Terrance Armentrout On second thought......GFYourself!
Just want to add that both the vented examples that were drawn act as air pumps, one relies on just centrifugal forces while the other uses a bend to assist and to possibly also increase surface area inside the vents.
Wow I always just assumed drilled was the best, just because everyone uses them on their high end cars. I guess I know why the P1 has those big plain vented rotors now.
Pakman332 Maclaren P1 is one of the very few supercars cars that doesn't use drilled rotors
Jonny Oliveira yeah I know, that's what I said. They are just vented.
They are looking for a performance characteristic which considers brake pads and rotor material. Be careful on assuming one way or another.
I did put cross drilled rotors on my Prius. They work great.
Now I love your channel....but this is a "SHOUTOUT".... to all americans....You can clearly see with your own eyes, that there is NO rotor.....IT IS A DISC!!!!! BREAK DISCS!!!!!......the rotor is the shaft.
PS... Gotta say, thanks again for some great info & no nonsense opinion. best car info IMO.
Every plain surface rotor I had on my cars very quickly warped - usually before the first pad change. The drilled/slotted rotors have never warped on me - even after a couple of pad changes (didn't have a chance to check the performance beyond that as I got a new car which came stock with plain rotors).
Mono block vs two piece calipers
Lol I know monoblocks, but he should do a video on it
+Euge Lymbers Dont you mean floating and fixed?
+Daniel Kerkotchian same thing, I've heard both I like the name monoblock better though
+Euge Lymbers what's the difference between them?
+Bart Van Riel two piece sliding calipers are your standard everyday caliper that most cars have, they usually have one or two Pistons on one side, mono block fixed calipers a solid one piece with 4-6 Pistons with a 50/50 split have Pistons on both sides these brakes are much better because they are solid so no sliding parts which means less flex and normally have more Pistons pushing the pads, like AMGs Ferraris and Porsches have monoblock fixed calipers
Great video. If I might add, drilled rotors are also 'noisy' when the braking system of a given car, isn't engineered for their application. Slotted is always the way to go, in my opinion.
Break pad please!!
CY YEUNG Soon enough!
Engineering Explained thank you!
i have black diamond over size 308 mil drilled and grooved vented disks, they last years and give awsum braking performance. I have never had issues with cracks it all comes down to the quality of your disks more than anything.. but drilled works and combi like mine witch it grooved and drilled is simply awsum!!
My grandma uses slotted drilled rotors on her wheelchairs and every time she stops her wig, false teeth and depends underwear fly off.
I had cross drilled rotors for ten years without issues. Heat differential only becomes relevant in hard track racing. No street driven criss drilled rotor will ever get hot enough for it to be an issue. For street applications they are a huge improvement with zero chance of failure