How'd you manage to survive the sleepless nights working on a project or a report whilst memorizing a ton of formulas and laws? And How long did it take you to finish?, I've spent 5 years in an engineering University, I should be graduating after next semester but im held back for maybe about 2 more years.
I’m a retired mechanical engineer. I worked with power systems for 42 years. Love these videos. Great teacher. Heartwarming to encounter a great young engineer!
I am an engine Mechanic and certified technician for Ford. Were you a Ford engineer? Because if so....WE NEED TO HAVE A CHAT! Working on current Fords we hate the engineers 😆 🤣 😂
OHC simply means overhead cams, which includes SOHC. Though both are fairly good at decently high RPM, DOHC will allow for a bit more control, thus helping at higher RPMs.
Just stumbled across your videos for the first time and have watched several. Good stuff. I've been playing with cars for almost 40 years and you have cleared up some concepts for me. Thank you.
@@CA-qv2cz I don't know how a person with 40 years experience working on cars, even their personal cars only, could not understand OHV, SOHC and DOHC and the benefits of each design.
Always a good time! Actually when I arrived in Maranello they were testing the 458 on the Fiorano circuit. This was in 2010 when the 458 was still brand new. Awesome sounds.
Thanks. Good video. I just bought an SRT and wanted to understand the pushrods engine better. I know they're old fashioned but I wanted to understand their advantages as outside of the German v8s, pushrods seem very common still, regardless of age
There's a chain or belt linking the crankshaft to the camshafts. It's geared 2:1 so for every two revolutions of the crankshaft, the camshaft rotates once.
Single Cam has two lobes per cylinder. Each opens and closes one valve. usually in a Single Cam setup it's two valves per cylinder. So for example a regular 4 cylinder has 8 valves. Each lobe will hit a valve. Either intake or exhaust. Hope this clears things up for you!
The single overhead camshaft on my bike pushes 2 valves per cam, with a rocker that splits into 2 ends to push 2 valves. Was quiet a funny thing to find
Just wanted to point out that most heavy duty Diesel truck engines are SOHC (they're actually called "cam-in-head", but the cams are kind of "over the head" so it's really a moot point IMO) with 4 valves per cylinder, such as the C15, X15, and DD15. One lobe opens both intake valves, the other opens both exhaust valves. On C15's there are three lobes for every cylinder, and the rocker arms that the third (middle) lobes actuate push down on the injectors in order to build pressure in the injectors for injecting the fuel. As another example, Caterpillar's 13L and smaller engines (all Diesel) are pushrod engines but still have 4-valve valvetrains. Instead of the typical arrangement with intake valves being on the left or right and the exhaust valves being on the right or left, heavy duty OHV Diesel engines will typically have one intake valve and one exhaust valve on the left side and another intake and exhaust valve on the right. Many Cummins ISX engines came with DOHC setups, but it's not your typical DOHC engine with one cam for the intake valves and one cam for the exhaust valves. The ISX's with twin cams had one camshaft actuating all of the intake and exhaust valves with the other pushing on the injectors.
I was actually shocked to find out that the current Honda Insight uses SOHC along with only 8 valves. To me it just looked like they're going backwards, but perhaps it was cost effective. It also has a relatively low (compared to competitive vehicles) compression ratio of 10.8:1.
First time I truly understood what all those DOHC, SOHC and OHV labels mean while playing Car Mechanic Simulator 2018. Thank you. Subscribed instantly.
I believe Ferrari has had some 5 valve engines as well. It's likely that the benefit is minimal from the associated cost. More moving parts, higher complexity, and at what gain?
Because it costs a good amount to change over. Also, pushrod engines tend to be a bit more compact. Ultimately, I do believe they will be phased out. They're pretty rare in current production vehicles.
You have better airflow - you bring in air, and push it out, more easily. This in turn can increase volumetric efficiency (especially at higher RPM), meaning you have more oxygen to use, and can make more efficient use of your cylinders.
I don't know why youtube suggested this old video but it's fun to see how far you've come in your production quality. Great information even though the audio and lighting were not optimum.
Yes, it is a dohc set-up, except on the mustang the timing of the cams rotation can be altered hence the name "twin independent variable camshaft timing." Pretty cool technology, allows the camshaft to rotate slightly from its original point, meaning it can vary the opening and closing of the valves for different purposes, fuel economy, or power.
They are awesome! Allows for a square step function rather than sinusoidal, meaning the valves can stay completely open longer than they can with camshaft based engines.
Good suggestion, perhaps eventually. For now just do an image search on google for "spark plug different colors." There are a ton of useful images that show what the different colors mean.
There's a belt or chain (depending on the car) that is connected to both the camshaft and the crankshaft, so the crankshaft drives the camshaft. Also important to know that this gear ratio is 2:1 crank:cam. For every 2 rotations of the crankshaft the camshaft will revolve 360 degrees.
A bit late but I really like how you used the resources you had and created this video, it's so amazing and actually helpful, I hope your doing well 8 years later
The LS is a decently small package, but it falls under my category of "inherently reliable" by having high volume and relatively low power - means less stress on the engine. I wouldn't categorize it as efficient though.
@LongRangeBullet Yes, exactly. This is where the valves do not entirely close during the rest of the engine cycle other than the cycle they are needed for.
Extremely grateful for these videos youve made...I learned more in twenty minutes than ive learned in 6 years working at an auto parts store...You, my friend, are the best of the best!
Thoughts: * Semantics: Two valves per cylinder is NOT less efficient. It breathes less efficiently at high engine speeds, but it usually actually breathes more efficiently at low engine speeds. This depends on how the engine is tuned of course; I've read [cannot remember where, sorry] that a 4-valve system will only produce about 2-5% more ultimate peak power than a 2-valve system on top of the same block when both are maximized for lift and duration. In modern automotive use, 4-valve engines are primarily used because they can give the same high rpm breathing efficiency as a maximized 2-valve head while using less overlap and far lower lift, thus making it easier to meet emissions standards while still making the same ultimate horsepower. Thus the 4-valve head in street car use is there to meet emissions standards, not to make more power. * OHV or pushrod valve trains typically use more moving parts than a SOHC/DOHC valve train. This is why very high rpm engines invariably use OHC for valve operation. YES you can make a 10,000 rpm pushrod engine work. Try making it work for a production car, which has to run for 200,000 miles and has to be [most importantly!] CHEAP to produce. That's a tall order, and that is also why pushrods are only used on [relatively] low rpm large displacement V8 engines, though there is some overlap. -Remember now....the vast majority of automotive engineers spend their time at work not trying to build a better or more fascinating car; The majority spend all their time at work as process engineers trying to figure out ways to produce that car....CHEAPER. * Most German [and most other, for that matter] SOHC engines use bucket tappets, where the camshaft acts upon the lifter itself, and the lifter acts upon the stellite tip of the valve. Rocker arms are used in many SOHC Honda engines, but for the most part SOHC engines don't have the rocker arms you've shown. Great videos! Keep up the good work.
5.7 Liter Toyota DOHC 32V = 66 HP per liter, 5.3 Liter OHV 16V = 66 HP per liter, 5.7 liter OHV 16v hemi = 69 HP per liter. So where is the increased efficiency? Through experience I can tell you the only thing the 32 valve v8 did was use more fuel and make more noise
@@Av8tor952 Have you ever heard of resistance to knock? DOHC allows a natural hemispherical head. As to the meat of your post, the output per CC depends upon the timing of the valves, their lift, the intake, the compression ratio, et cetera. OHC will always be the better choice since it revs better. And there are fewer parts to make. And fewer parts to break... Take a look at Hoovie's Garage, where he shows what happens when one installs a pushrod Chevy V8 engine in a Porsche 911. It broke almost immediately, and this was a crate engine.... Hello?
Flies2FLL please explain for the class how 4 cams are fewer than one, 32 valves are fewer than 16 and 32 lifters are fewer than 16. I’m not suggesting there isn’t a benefit to ohc multi-valve engines. Only that the blanket statement ohc/4 valve engine is more efficient does not hold true in the the three examples I provided
Wrong, DOHC engines do make more power for their displacement. Take a DOHC v8 and size it the same as a ohv engine it will make more power because it makes more per cubic inch. Ford's 3.0 dohc v6 is a perfect example of this when compared to gm' s 3.8 ohv v6. Both make 200-205 hp but ones smaller, size it to 3.8l and you have 260hp. LT5 ZR1? Oh how short the memory of gm fanboys are.
@@Av8tor952 DOHC V8 engines have 32 Valves, and four cams, 36 total parts OHV V8 engines have 16 Pushrod s, 16 Lifters, 16 Valves and one camshaft 49 total parts
I've heard both used. Regardless of the letter, the numbers are the only thing which hold much meaning, representing the viscosity of the oil at cold (first number) and elevated temperatures (second number).
What are your thoughts on how the Chevrolet LS engine series, and even more so the new LT1 in the 2014 Corvette Stingray and LT1 in the 2015 Z06 are so much better than their predecessors and able to make incredible power reliably and achieve decent gas mileage as well? I think you should do a video on that. The LS engines are just amazing. Think about the Hennessey Venom GT with a 1200hp LS3 that went 270mph.
Performance? Corvette (pushrod engine) 460hp/6.2l=74.19 hp/liter compared to a Hyundai Genesis (DOHC) 3.8L 348hp/3.8l= 91.58 hp/liter Pretty much any DOHC has higher specific output vs the most powerful pushrod engine designs. Purpose built DOHC turbocharged engines (Toyota Supra) can have more then 1200hp with less then half the displacement of an LS3. Take a 2015 ZO6 and drive it around like any real person would and come back here and post you think that it still gets decent gas mileage. GM performance is an oxymoron. Ignorance isn't an excuse.
inline whine try a Ford 5.0 Coyote V8 that is 4v DOHC, puts these other american motors to shame. stock comes with 435 hp 400 torque but ive seen built ones that are still 5.0 make 575 whp all motor in road race cars (theres probably higher but that is a good example). ive seen them getting 29-30 mpg highway which is pretty good. they turboed a new coyote 2015 model motor and with twin 62s? and just 16.5 psi it made 950 whp stock internals no problems. while i like the 2jz i think the 2015/ boss 302 version of the coyote is simply a better motor (20 + years newer and doesnt need a shit ton of boost for 950 whp)
Yes that is why they were really made for the 2 intake vales could also stay open for longer. As the first intake valve closes it is followed by the second valve. Giving a longer time to stay open. 60 and 70 f1 tech.
Something I think you're missing with your analysis is that an OHV allows a lot more displacement per unit of external size. For example, a 6L LS2 engine is about the same size on the outside as a 1.8L DOHC Mazda BP engine. Thus, if you want to put 400 hp in the small engine bay of your sports car, you can have a very mildly tuned 6.0L V8 with fuel economy friendly camshafts and low levels of stress throughout the system or you can have a timebomb turbo 1.8L that gets 12 mpg and doesn't pass emissions. This is actually a huge point. For mpg, rpm are very bad. With these low stressed OHV designs, you can run much lower rpm and get better fuel economy than with a smaller displacement OHC engines. LS swapped Miatas, for example, almost always get better fuel mileage than stock Miatas, in spite of doubling/tripling the power and more than tripling the displacement.
+The real doktorbimmer I'm afraid most of this is verifiably false. Can you find a remotely affordable production engine that delivers more power per pound than a pushrod LS? LS7 weighs 430 pounds and makes 505 hp. It also gets 16/26 mpg and is tiny. The only contemporary (as in designed around the same time as the LS7) DOHC design I can find that's competitive is the Ferrari 430 engine. A Ferrari 4.3L V8, which is an order of magnitude more expensive, weighs 408 pounds and makes 483 hp. It also gets an incredibly awful 11/16 mpg and is larger. A lower budget, non-performance example is the Buick 3.8L V6. Compared to other V6 engines of the late 90s and early 2000s, it is lighter, smaller and more fuel efficient than competing DOHC designs. For example, here is a comparison of a OHV Buick LeSabre automatic with competing (universally more expensive and newer design) DOHC V6 cars with automatics. All are about the same weight, all have 4 speed transmissions. You will find the LeSabre gets the best mpg. You will also find the LeSabre engine makes similar power, is lighter and much smaller. Unlike its competitors, it also doesn't require premium fuel. www.cars.com/go/compare/modelCompare.jsp?myids=30,5,280,156 Or, if you prefer trucks, compare a modern Chevrolet/Chrysler OHV truck's fuel consumption with the "modern" DOHC V8 designs from Nissan, Ford or Toyota. OHV does not have significantly different BSFC. Pushrod engines have a disadvantage in power per unit of displacement. Fortunately, that really isn't a very important metric. Finally, I want to show just how enormous the size advantage is for OHV designs. This first picture is a comparison of a 1.8L DOHC four cylinder engine (Mazda B Series) with 140 hp that tops out at 25 mpg with a 6.0L OHV eight cylinder engine (LS2) that will exceed 30 mpg. You will find they are almost exactly the same external size. www.onallcylinders.com/wp-content/uploads/2015/03/tboltEP3_03.jpg Here is a DOHC 3.5L V6 (Vq35) compared with a 5.7L OHV V8 (LS6). The OHV design is, of course, more powerful and gets better mpg. i.kinja-img.com/gawker-media/image/upload/s--58IrBUdM--/18keof9iqsd24jpg.jpg
in school for mechanical engineering one day i want to open a car shop specializing in aftermarket customization and concept design to working models and i actually didnt event watch the video yet but i see this is like...GREAT SO THANKS FOR THIS CHANNEL!
I dont understand on SOHC how it opens the intake valve if the cam shaft pushed down on the rocker arm then the left side will go up instead of opening. Opposite of the exhaust valve.
The cam can push up on the rocker arm from underneath for it to pivot and press down the exhaust valve for the air to get out. As the cam goes around, it also is able to push down on the rockerarm from above enabling the valve to be pushed down for the intake air to come in. It's a bit weird / confusing seeing it drawn on a board, since its in 2D, but that's how it works.
Not necessarily, the optimum times for the camshaft to open the valves may differ at different rpm, and having variable camshaft timing allows for the timing of the cams to differ slightly, changing the overlap between exhaust and intake.
Damn I don't understand this I guess I need to learn the basics. Where can I learn about modding cars or even basic things like valves intake i got like no clue yes I know ima noob just starting to like cars more. Any website anyone?
Omoiyari23 I know this is 4months old but before learning about modding cars or in order to do so you first need to learn about how a car engine works, because this video is very basic. Good luck, its a very interesting world.
There may be slight differences in the material, the basic operation is the same. Diesels do not have throttle bodies so that's also another difference with the intake system.
You forgot to mention that DOHC engines have more friction torque than a pushrod engine. they have very complex timing chains and more rotating mass. You also kept calling the camshaft a cylinder instead of saying its a base circle with a lobe on it.
They don’t necessarily have more friction. Remember that the load on the cam lobes and cam bearings has a HUGE effect on friction. And they are MUCH higher in a pushrod engine because (1) two valves per cylinder means large valves with heavy springs, (2) those springs must return the valve, rocker, pushrod, AND lifter to their original position, which makes them even heavier, and (3) with two valves per cylinder and port restriction from pushrod well interference, valve lift must be higher than with four valves to get the same flow. By contrast, OHC may have more valves and possibly cams. But bearing and cam lobe load is MUCH lower.
@@matthewstorm5188 Load is much different than friction. There is still a film of oil between that "load." The biggest loss on a 4 stroke engine is the compression stroke which is a different topic. However, you can never tell me more moving parts is always better. Have you not seen the flow numbers of big square port lsx cylinder heads that are pushrod engines? Lets take the coyote vs ls3 for example. At .500 lift the ls3 OHV flows 318/234. The coyote flows 289/201. However coyote is a smaller engine with smaller ports. But its clear your thesis is not exactly correct. Both types of engines have their place. However if I'm building a racing engine, I'll take the one that produces the most cubes, weighs less, smaller, with less moving parts. And thats hands down a pushrod engine
Your a fine young man. America is still producing youth with practical knowledge. My late brother was a master mechanic and you and he would have hit it off.
I like this kid and think he does a good job with these videos. I think that, like all of us, he's a product of his time. I say that because he states unequivocally the overhead cam (valve) engine is better than the tried and true OHV. Since he's an engineer he should know nothing is that simple and nothing is written in stone. He's grown up with small, four cylinder engines the kind that surged in popularity in the wake of the 1974 OPEC oil embargo and accelerated the fall of Detroit. In fact, I agree with his preference for DOHC as it applies to "four bangers." However, for people who need or just love beefy V8 engines, we're more than happy with the numerous benefits that our pushrod (OHV) engines have over DOHC. Those benefits are nicely explained here: www.ebay.com/gds/DOHC-SOHC-OHV-valvetrains-whats-the-difference-/10000000002220885/g.html IMHO I think this young engineer is only about half right. Maybe that's because he's never had to pull a big heavy trailer cross country, or maybe he's never needed a 15 passenger van? If you read the linked article, you know there are very good reason they still build OHV engines. Again, I like his videos, and I think he's good at making them. My only suggestion is always try to be careful not to let personal preferences cloud objectivity.
A light bulb just illuminated above my head! Thanks man! As an interested enthusiast who wants to understand how my GSXR works, I appreciate your videos.
I do not believe that to be correct. OHV refers to the valves being over the top deck of the motor. Or other words, the piston at top dead center. The term was designed to refer to motors that were not original flat head motors.
Greg Bates This is an interesting description: en.wikipedia.org/wiki/Overhead_valve_engineen.wikipedia.org/wiki/Overhead_camshaft In OHC the cam is on top of the head, in OHV the cam is connected to the crank with the timing chain below the head and push rods activate the valves which are above the head. In OHC engines the valves are also above the head, which can make the designation confusing, but the cam, usually driven by a belt connected to the crank, activates the valves directly.
Yeah, but that's like calling a square a "parallelogram." I mean, it is...but it's sorta implied that when you call something a parallelogram, you're talking about something that doesn't "make the cut" as a rectangle or square.
WOW just stumble into this on 6 Sept 2021. Nice to see how far you've come. You should do some retrospective videos blending your old videos with new style
I would assume the reasoning is that drag cars typically have large engines, and large engines are low revving (relative to smaller engines) so pushrods do the trick at low rpms. Also the oil you use with pushrods is a lot more lenient.
Standing by to see people swapping out their LS motors for an ohc 4 cylinder to go faster, lmfao. Hate on pushrod all you want, I'll be keeping an eye on you in the rear view as you keep talking about hp/liter, and pretend area under the curve doesn't exist. Real world results > theorycrafting, every damn time.
Jeff Smith a 2jz will still make more power than any ls motor and its only like 3 liters so swapping out your ls for a dohc 2jzgte would definitely be better😂😂
The fact is per cubic inch DOHC engines beat ohv for power output, size that ohv engine up to the same size as the ohv and it will absolutely make more power. Apparently the LT5 ZR1 us some thing gm fanboys like to ignore.
@@vernonknight8611 you're talking about a racing engine first of all not a production engine, secondly if that engine used the same bore and stroke but was dohc it would make more power. You can't get around the physics.
There is another cam lobe behind (think into the whiteboard) the first lobe which operates the exhaust valve for that particular cylinder, with the lobe in front on it (on the camshaft) operating the intake valve.
Sure it's possible, the 5.0 in the Mustang is doing it. I just mention that one because it's common, plenty of V's use DOHC and have for a while. More complicated? Perhaps, but the Mustang's redline tells you it comes with benefit!
@@MARTPEREfor the sake of racing and performance. Hp matters more than torque for racing. That engine is geared more towards racing than, street. This is self evident in drag cars which have really "peaky engines" with relatively low torque and insane hp numbers.
really have to give thumbs up, great explanation! I deal in small engines, mostly antique flathead and am building my knowledge about all different kinds. Ofc, things like dual cam are generally not applicable for them, but still appreciate getting to learn about engines in general 👍
Good on ya mate. It's good to see people with auto mechanical knowledge do not always need to smoke a pipe, nearing retirement with black fingers and mountains of facial hair. Congrats for youtube partner acceptance. Clear presentation. All the best, Mark. UK
Right, but the reason is that it's much easier to push air out than it is to pull air in. A closing cylinder (piston moving up) the air must escape. As the piston moves down on intake, a partial vacuum is created, and this pulls in the air, which isn't as easy of a task.
Well, essentially this happens regardless of the cam design, but two cams allows for more tweaking of the timing. And when you say "pulled" it's simply the valve spring pushing the valve closed.
I've got the OHV 4.0liter V6 by Ford in in my '98 4x4 Explorer. 250,000+ miles and still running strong. I typically use Castrol GTX 20W50 + Lucas oil. You can hear a lifter on start ups or a loose timing tensioner but the motor does not give up. It still produces great power and throttle response. Built Ford Tough. -TX
There are only more springs if there are more valves, and more valves means better airflow. The greater the area that air is allowed to come in, the easier (and greater amount of air) it is for the air to come in. Better airflow = more power with the same engine, meaning the engine is more efficient at producing power. Yes, the effects will be noticed more at higher rpm, but that doesn't change the principle.
I find this very good and informing . I thought I new about these things ,but not this clear in my mind how each one workedThank you so much , mr clever
I'm a fan of small, powerful, and efficient engines. Emphasis on efficient. If it can be done with less weight and less volume, power to it. That said, there are some inherent reliability benefits of a high volume relatively low powered engine.
Who are you replying to? I've seen this kind of thing before on TH-cam comments. Is it because back in the day, TH-cam didn't have a "reply" function for comments, so you had to just leave a comment directed at someone and hope they know who you're talking to? This interests me.
I was bored in the beginning, but as you advanced, it became interesting. Also worth mentioning is that if you want a smooth ride at higher RPMs , you'd rather go with OHC instead of an OHV. an example is Lexus, which uses DOHC in its V8s and doesn't have to increase the wheelbase in its cars to get a smoother ride it's known for
@ThunderViktor As long as you find something that fits, I see no problem. I actually had a friend with a 2000 Focus who also had to replace the engine. I'm not sure what engine you plan on replacing it with, but DOHC is the modern valvetrain style.
This was Engineering Explained back in 1973.
Lol
lmao
That comment has made my day!
And in 2020
Colorized remastered
I have graduated my friend, BSME!
How'd you manage to survive the sleepless nights working on a project or a report whilst memorizing a ton of formulas and laws? And How long did it take you to finish?, I've spent 5 years in an engineering University, I should be graduating after next semester but im held back for maybe about 2 more years.
Redue this video!!
Redo this video, its BORING
This guy aged 30 years in 7 years...
Can't believe this was 9-10 years ago
I’m a retired mechanical engineer. I worked with power systems for 42 years. Love these videos. Great teacher. Heartwarming to encounter a great young engineer!
Tell me your secrets mountain climber I just want to know the truth
I am an engine Mechanic and certified technician for Ford. Were you a Ford engineer? Because if so....WE NEED TO HAVE A CHAT! Working on current Fords we hate the engineers 😆 🤣 😂
Nice drawings. I like the funny robot in the middle.
hahahahaha
Scrolled down looking for this comment haha
daemonllama78 same here
Žilvinas Deveika it's not a funny robot! It's a diagram of a cylinder with an SOHC valve-train!
Aw snap. Why did you have to ruin it for me? : (
OHC simply means overhead cams, which includes SOHC. Though both are fairly good at decently high RPM, DOHC will allow for a bit more control, thus helping at higher RPMs.
Just stumbled across your videos for the first time and have watched several. Good stuff. I've been playing with cars for almost 40 years and you have cleared up some concepts for me. Thank you.
Elmo Fuddleputt Glad you enjoy them! Thanks for watching. :)
YoU recommend what tools necessary to 'play'around w/ a cylinder head
I love your profile picture!
Jesus Christ I hope you only worked on your personal vehicles
@@CA-qv2cz I don't know how a person with 40 years experience working on cars, even their personal cars only, could not understand OHV, SOHC and DOHC and the benefits of each design.
Always a good time! Actually when I arrived in Maranello they were testing the 458 on the Fiorano circuit. This was in 2010 when the 458 was still brand new. Awesome sounds.
Thanks. Good video. I just bought an SRT and wanted to understand the pushrods engine better. I know they're old fashioned but I wanted to understand their advantages as outside of the German v8s, pushrods seem very common still, regardless of age
Pushrod, SOHC, and DOHC all predate World War I though, so saying "one is old fashioned" is a bunch of garbage.
Damn, this my new fav channel on TH-cam.
Thanks!
There's a chain or belt linking the crankshaft to the camshafts. It's geared 2:1 so for every two revolutions of the crankshaft, the camshaft rotates once.
Literally everything you say in your videos makes sense. I just wish that teachers could do the same. Great work!
Watching this guy currently in 2021 and seeing this from nine years ago is crazy. This guy does not age!
Correct, and the costs are still relatively equal, with the Mustang getting slightly better highway fuel economy.
Single Cam has two lobes per cylinder. Each opens and closes one valve. usually in a Single Cam setup it's two valves per cylinder. So for example a regular 4 cylinder has 8 valves. Each lobe will hit a valve. Either intake or exhaust. Hope this clears things up for you!
The single overhead camshaft on my bike pushes 2 valves per cam, with a rocker that splits into 2 ends to push 2 valves. Was quiet a funny thing to find
Not all sohc some have 3v
@@haroldtollison3363 mine have 4v by cyl...honda 1.5L 16v SOHC
Just wanted to point out that most heavy duty Diesel truck engines are SOHC (they're actually called "cam-in-head", but the cams are kind of "over the head" so it's really a moot point IMO) with 4 valves per cylinder, such as the C15, X15, and DD15. One lobe opens both intake valves, the other opens both exhaust valves. On C15's there are three lobes for every cylinder, and the rocker arms that the third (middle) lobes actuate push down on the injectors in order to build pressure in the injectors for injecting the fuel.
As another example, Caterpillar's 13L and smaller engines (all Diesel) are pushrod engines but still have 4-valve valvetrains. Instead of the typical arrangement with intake valves being on the left or right and the exhaust valves being on the right or left, heavy duty OHV Diesel engines will typically have one intake valve and one exhaust valve on the left side and another intake and exhaust valve on the right.
Many Cummins ISX engines came with DOHC setups, but it's not your typical DOHC engine with one cam for the intake valves and one cam for the exhaust valves. The ISX's with twin cams had one camshaft actuating all of the intake and exhaust valves with the other pushing on the injectors.
Does it always have 2lobes per cylinder, or is it just alot more common?
Even 5 years ago you were still a fuckin genius. P.S love your videos
your sohc diagram reminds me of squidward from sponge Bob. good video, thanks.
I was actually shocked to find out that the current Honda Insight uses SOHC along with only 8 valves. To me it just looked like they're going backwards, but perhaps it was cost effective. It also has a relatively low (compared to competitive vehicles) compression ratio of 10.8:1.
First time I truly understood what all those DOHC, SOHC and OHV labels mean while playing Car Mechanic Simulator 2018. Thank you. Subscribed instantly.
I believe Ferrari has had some 5 valve engines as well. It's likely that the benefit is minimal from the associated cost. More moving parts, higher complexity, and at what gain?
Because it costs a good amount to change over. Also, pushrod engines tend to be a bit more compact. Ultimately, I do believe they will be phased out. They're pretty rare in current production vehicles.
You have better airflow - you bring in air, and push it out, more easily. This in turn can increase volumetric efficiency (especially at higher RPM), meaning you have more oxygen to use, and can make more efficient use of your cylinders.
I don't know why youtube suggested this old video but it's fun to see how far you've come in your production quality. Great information even though the audio and lighting were not optimum.
Yes, I'm surprised this hasn't been requested more frequently. Eventually!
Yes, it is a dohc set-up, except on the mustang the timing of the cams rotation can be altered hence the name "twin independent variable camshaft timing." Pretty cool technology, allows the camshaft to rotate slightly from its original point, meaning it can vary the opening and closing of the valves for different purposes, fuel economy, or power.
clear my confusion about relationship between cam and push rod.tks
They are awesome! Allows for a square step function rather than sinusoidal, meaning the valves can stay completely open longer than they can with camshaft based engines.
OHV: The valvetrain of choice for lawnmowers, power washers, and GM's 'cutting-edge' design department.
Good suggestion, perhaps eventually. For now just do an image search on google for "spark plug different colors." There are a ton of useful images that show what the different colors mean.
DAT A/C VTEC KICKED IN YO 4:07
There's a belt or chain (depending on the car) that is connected to both the camshaft and the crankshaft, so the crankshaft drives the camshaft. Also important to know that this gear ratio is 2:1 crank:cam. For every 2 rotations of the crankshaft the camshaft will revolve 360 degrees.
In addition to the advantages I have pointed out, the image in your profile picture features a car with overhead cams. :)
A bit late but I really like how you used the resources you had and created this video, it's so amazing and actually helpful, I hope your doing well 8 years later
Genuinely insightful- but why do odd (3/5) numbers of valves help smooth flow?
The LS is a decently small package, but it falls under my category of "inherently reliable" by having high volume and relatively low power - means less stress on the engine. I wouldn't categorize it as efficient though.
LOL this guy was used in a vine where he talks about "boost" " I don't need it, I definitely don't need it"
"I NEED IT !"
+leslie huang haha yep! #RIPVine
Engineering Explained yo sick vids!!!! Keep it up!!!
@LongRangeBullet Yes, exactly. This is where the valves do not entirely close during the rest of the engine cycle other than the cycle they are needed for.
That was really useful and I really appreciate you, thanks bro
Happy to hear it, thanks!
Extremely grateful for these videos youve made...I learned more in twenty minutes than ive learned in 6 years working at an auto parts store...You, my friend, are the best of the best!
Thoughts:
* Semantics: Two valves per cylinder is NOT less efficient. It breathes less efficiently at high engine speeds, but it usually actually breathes more efficiently at low engine speeds. This depends on how the engine is tuned of course; I've read [cannot remember where, sorry] that a 4-valve system will only produce about 2-5% more ultimate peak power than a 2-valve system on top of the same block when both are maximized for lift and duration. In modern automotive use, 4-valve engines are primarily used because they can give the same high rpm breathing efficiency as a maximized 2-valve head while using less overlap and far lower lift, thus making it easier to meet emissions standards while still making the same ultimate horsepower. Thus the 4-valve head in street car use is there to meet emissions standards, not to make more power.
* OHV or pushrod valve trains typically use more moving parts than a SOHC/DOHC valve train. This is why very high rpm engines invariably use OHC for valve operation. YES you can make a 10,000 rpm pushrod engine work. Try making it work for a production car, which has to run for 200,000 miles and has to be [most importantly!] CHEAP to produce. That's a tall order, and that is also why pushrods are only used on [relatively] low rpm large displacement V8 engines, though there is some overlap.
-Remember now....the vast majority of automotive engineers spend their time at work not trying to build a better or more fascinating car; The majority spend all their time at work as process engineers trying to figure out ways to produce that car....CHEAPER.
* Most German [and most other, for that matter] SOHC engines use bucket tappets, where the camshaft acts upon the lifter itself, and the lifter acts upon the stellite tip of the valve. Rocker arms are used in many SOHC Honda engines, but for the most part SOHC engines don't have the rocker arms you've shown.
Great videos! Keep up the good work.
5.7 Liter Toyota DOHC 32V = 66 HP per liter, 5.3 Liter OHV 16V = 66 HP per liter, 5.7 liter OHV 16v hemi = 69 HP per liter. So where is the increased efficiency? Through experience I can tell you the only thing the 32 valve v8 did was use more fuel and make more noise
@@Av8tor952 Have you ever heard of resistance to knock? DOHC allows a natural hemispherical head. As to the meat of your post, the output per CC depends upon the timing of the valves, their lift, the intake, the compression ratio, et cetera. OHC will always be the better choice since it revs better. And there are fewer parts to make. And fewer parts to break...
Take a look at Hoovie's Garage, where he shows what happens when one installs a pushrod Chevy V8 engine in a Porsche 911. It broke almost immediately, and this was a crate engine....
Hello?
Flies2FLL please explain for the class how 4 cams are fewer than one, 32 valves are fewer than 16 and 32 lifters are fewer than 16. I’m not suggesting there isn’t a benefit to ohc multi-valve engines. Only that the blanket statement ohc/4 valve engine is more efficient does not hold true in the the three examples I provided
Wrong, DOHC engines do make more power for their displacement. Take a DOHC v8 and size it the same as a ohv engine it will make more power because it makes more per cubic inch. Ford's 3.0 dohc v6 is a perfect example of this when compared to gm' s 3.8 ohv v6. Both make 200-205 hp but ones smaller, size it to 3.8l and you have 260hp. LT5 ZR1? Oh how short the memory of gm fanboys are.
@@Av8tor952 DOHC V8 engines have 32 Valves, and four cams, 36 total parts OHV V8 engines have 16 Pushrod s, 16 Lifters, 16 Valves and one camshaft 49 total parts
I've heard both used. Regardless of the letter, the numbers are the only thing which hold much meaning, representing the viscosity of the oil at cold (first number) and elevated temperatures (second number).
What are your thoughts on how the Chevrolet LS engine series, and even more so the new LT1 in the 2014 Corvette Stingray and LT1 in the 2015 Z06 are so much better than their predecessors and able to make incredible power reliably and achieve decent gas mileage as well? I think you should do a video on that. The LS engines are just amazing. Think about the Hennessey Venom GT with a 1200hp LS3 that went 270mph.
Johnny Cash I'm guessing you've already seen this? Corvette Z06 (LT4) and Camaro Z/28 (LS7) Engine Build
lol stupid Americans always over hyping the piece of shit gm cars its so annoying
AVillarHD
please feel free to share what it is that you drive that makes your car so much better
Performance? Corvette (pushrod engine) 460hp/6.2l=74.19 hp/liter compared to a Hyundai Genesis (DOHC) 3.8L 348hp/3.8l= 91.58 hp/liter Pretty much any DOHC has higher specific output vs the most powerful pushrod engine designs. Purpose built DOHC turbocharged engines (Toyota Supra) can have more then 1200hp with less then half the displacement of an LS3. Take a 2015 ZO6 and drive it around like any real person would and come back here and post you think that it still gets decent gas mileage. GM performance is an oxymoron. Ignorance isn't an excuse.
inline whine try a Ford 5.0 Coyote V8 that is 4v DOHC, puts these other american motors to shame. stock comes with 435 hp 400 torque but ive seen built ones that are still 5.0 make 575 whp all motor in road race cars (theres probably higher but that is a good example). ive seen them getting 29-30 mpg highway which is pretty good. they turboed a new coyote 2015 model motor and with twin 62s? and just 16.5 psi it made 950 whp stock internals no problems. while i like the 2jz i think the 2015/ boss 302 version of the coyote is simply a better motor (20 + years newer and doesnt need a shit ton of boost for 950 whp)
Nice and compact, pros and cons and also well spoken. Thanky, I always wanted to understand the differences between DOHC, SOHC and OHV. +1
your a gun mate. best of luck for your career
Wow look at how far he has gotten in five years
*you're
Great video, 👍 thanks he talks for about 3 minutes about push rod, then about 90 seconds on sohc and about 90 seconds on Dohc
TOP VIDEOS VERY INFORMATIVE , THANK YOU VERY MUCH
Wow, this guys presentation skills have increased tremendously... bravo 👏👏👏
One other advantage of DOHC engines is that by having separate intake and exhaust cams, you can manipulate the timing between them.
+fukitol1972 Yeah, I was expecting him to mention that. Less compromises due to independent control.
Yes that is why they were really made for the 2 intake vales could also stay open for longer. As the first intake valve closes it is followed by the second valve. Giving a longer time to stay open. 60 and 70 f1 tech.
what advantage is their by varying the rates?
+The real doktorbimmer hmmm. So does that mean the Air-Fuel Ratio of 14.7:1 isn't always ideal?
@JCKustom13 Correct, if you don't need high revs then valve float is no issue, and OHV is a cheap and adequate way of achieving similar performance.
Something I think you're missing with your analysis is that an OHV allows a lot more displacement per unit of external size. For example, a 6L LS2 engine is about the same size on the outside as a 1.8L DOHC Mazda BP engine.
Thus, if you want to put 400 hp in the small engine bay of your sports car, you can have a very mildly tuned 6.0L V8 with fuel economy friendly camshafts and low levels of stress throughout the system or you can have a timebomb turbo 1.8L that gets 12 mpg and doesn't pass emissions.
This is actually a huge point. For mpg, rpm are very bad. With these low stressed OHV designs, you can run much lower rpm and get better fuel economy than with a smaller displacement OHC engines. LS swapped Miatas, for example, almost always get better fuel mileage than stock Miatas, in spite of doubling/tripling the power and more than tripling the displacement.
+Ben Garrido To be fair it does say "Compact" on his diagram.
+The real doktorbimmer I'm afraid most of this is verifiably false.
Can you find a remotely affordable production engine that delivers more power per pound than a pushrod LS?
LS7 weighs 430 pounds and makes 505 hp. It also gets 16/26 mpg and is tiny.
The only contemporary (as in designed around the same time as the LS7) DOHC design I can find that's competitive is the Ferrari 430 engine. A Ferrari 4.3L V8, which is an order of magnitude more expensive, weighs 408 pounds and makes 483 hp. It also gets an incredibly awful 11/16 mpg and is larger.
A lower budget, non-performance example is the Buick 3.8L V6. Compared to other V6 engines of the late 90s and early 2000s, it is lighter, smaller and more fuel efficient than competing DOHC designs.
For example, here is a comparison of a OHV Buick LeSabre automatic with competing (universally more expensive and newer design) DOHC V6 cars with automatics. All are about the same weight, all have 4 speed transmissions. You will find the LeSabre gets the best mpg. You will also find the LeSabre engine makes similar power, is lighter and much smaller. Unlike its competitors, it also doesn't require premium fuel.
www.cars.com/go/compare/modelCompare.jsp?myids=30,5,280,156
Or, if you prefer trucks, compare a modern Chevrolet/Chrysler OHV truck's fuel consumption with the "modern" DOHC V8 designs from Nissan, Ford or Toyota.
OHV does not have significantly different BSFC. Pushrod engines have a disadvantage in power per unit of displacement. Fortunately, that really isn't a very important metric.
Finally, I want to show just how enormous the size advantage is for OHV designs. This first picture is a comparison of a 1.8L DOHC four cylinder engine (Mazda B Series) with 140 hp that tops out at 25 mpg with a 6.0L OHV eight cylinder engine (LS2) that will exceed 30 mpg. You will find they are almost exactly the same external size.
www.onallcylinders.com/wp-content/uploads/2015/03/tboltEP3_03.jpg
Here is a DOHC 3.5L V6 (Vq35) compared with a 5.7L OHV V8 (LS6). The OHV design is, of course, more powerful and gets better mpg.
i.kinja-img.com/gawker-media/image/upload/s--58IrBUdM--/18keof9iqsd24jpg.jpg
While hostile, this isn't very well thought out.
And if you think Ferrari engines are less affordable than small block Chevies, man, I have a bridge to sell you.
+The real doktorbimmer dude, it's New Year's. Go be with your family.
in school for mechanical engineering one day i want to open a car shop specializing in aftermarket customization and concept design to working models and i actually didnt event watch the video yet but i see this is like...GREAT SO THANKS FOR THIS CHANNEL!
which is best ??
He explained that & really best for what? For speed? He said DOHC
You're welcome, keep me posted on the shop I'll make a visit. Good luck to you sir!
I dont understand on SOHC how it opens the intake valve if the cam shaft pushed down on the rocker arm then the left side will go up instead of opening. Opposite of the exhaust valve.
The cam can push up on the rocker arm from underneath for it to pivot and press down the exhaust valve for the air to get out. As the cam goes around, it also is able to push down on the rockerarm from above enabling the valve to be pushed down for the intake air to come in. It's a bit weird / confusing seeing it drawn on a board, since its in 2D, but that's how it works.
John Freeman Push it up the rocker arm and the opposite side goes down and open the valve.
Not necessarily, the optimum times for the camshaft to open the valves may differ at different rpm, and having variable camshaft timing allows for the timing of the cams to differ slightly, changing the overlap between exhaust and intake.
I wanna go back 12 years and ask him to marry me. 😂
Adorable
1. An object in motion stays in motion unless acted upon by an outside force.
2. More valves allow for greater air flow.
Damn I don't understand this I guess I need to learn the basics. Where can I learn about modding cars or even basic things like valves intake i got like no clue yes I know ima noob just starting to like cars more. Any website anyone?
Watch these playlists in order. Ask questions along the way! th-cam.com/users/EngineeringExplainedplaylists?view=50&sort=dd&shelf_id=2
Omoiyari23
I know this is 4months old but before learning about modding cars or in order to do so you first need to learn about how a car engine works, because this video is very basic. Good luck, its a very interesting world.
There may be slight differences in the material, the basic operation is the same. Diesels do not have throttle bodies so that's also another difference with the intake system.
You forgot to mention that DOHC engines have more friction torque than a pushrod engine. they have very complex timing chains and more rotating mass. You also kept calling the camshaft a cylinder instead of saying its a base circle with a lobe on it.
Rotating mass is better than oscillating mass, from an efficiency standpoint. And all engines will have some variant of timing chains/belts/gears.
*****
They don’t necessarily have more friction. Remember that the load on the cam lobes and cam bearings has a HUGE effect on friction. And they are MUCH higher in a pushrod engine because (1) two valves per cylinder means large valves with heavy springs, (2) those springs must return the valve, rocker, pushrod, AND lifter to their original position, which makes them even heavier, and (3) with two valves per cylinder and port restriction from pushrod well interference, valve lift must be higher than with four valves to get the same flow. By contrast, OHC may have more valves and possibly cams. But bearing and cam lobe load is MUCH lower.
@@matthewstorm5188 Load is much different than friction. There is still a film of oil between that "load." The biggest loss on a 4 stroke engine is the compression stroke which is a different topic. However, you can never tell me more moving parts is always better. Have you not seen the flow numbers of big square port lsx cylinder heads that are pushrod engines? Lets take the coyote vs ls3 for example. At .500 lift the ls3 OHV flows 318/234. The coyote flows 289/201. However coyote is a smaller engine with smaller ports. But its clear your thesis is not exactly correct. Both types of engines have their place. However if I'm building a racing engine, I'll take the one that produces the most cubes, weighs less, smaller, with less moving parts. And thats hands down a pushrod engine
Your a fine young man. America is still producing youth with practical knowledge. My late brother was a master mechanic and you and he would have hit it off.
I like this kid and think he does a good job with these videos. I think that, like all of us, he's a product of his time. I say that because he states unequivocally the overhead cam (valve) engine is better than the tried and true OHV. Since he's an engineer he should know nothing is that simple and nothing is written in stone. He's grown up with small, four cylinder engines the kind that surged in popularity in the wake of the 1974 OPEC oil embargo and accelerated the fall of Detroit. In fact, I agree with his preference for DOHC as it applies to "four bangers." However, for people who need or just love beefy V8 engines, we're more than happy with the numerous benefits that our pushrod (OHV) engines have over DOHC. Those benefits are nicely explained here: www.ebay.com/gds/DOHC-SOHC-OHV-valvetrains-whats-the-difference-/10000000002220885/g.html IMHO I think this young engineer is only about half right. Maybe that's because he's never had to pull a big heavy trailer cross country, or maybe he's never needed a 15 passenger van? If you read the linked article, you know there are very good reason they still build OHV engines. Again, I like his videos, and I think he's good at making them. My only suggestion is always try to be careful not to let personal preferences cloud objectivity.
A light bulb just illuminated above my head!
Thanks man! As an interested enthusiast who wants to understand how my GSXR works, I appreciate your videos.
All three scenarios are OHV.
I do not believe that to be correct. OHV refers to the valves being over the top deck of the motor. Or other words, the piston at top dead center. The term was designed to refer to motors that were not original flat head motors.
www.wordreference.com/definition/overhead-valve%20engine
Greg Bates This is an interesting description: en.wikipedia.org/wiki/Overhead_valve_engineen.wikipedia.org/wiki/Overhead_camshaft
In OHC the cam is on top of the head, in OHV the cam is connected to the crank with the timing chain below the head and push rods activate the valves which are above the head.
In OHC engines the valves are also above the head, which can make the designation confusing, but the cam, usually driven by a belt connected to the crank, activates the valves directly.
You are correct. You cannot not have an engine that is OHC that is NOT OHV.
Yeah, but that's like calling a square a "parallelogram." I mean, it is...but it's sorta implied that when you call something a parallelogram, you're talking about something that doesn't "make the cut" as a rectangle or square.
WOW just stumble into this on 6 Sept 2021. Nice to see how far you've come. You should do some retrospective videos blending your old videos with new style
can you please say it clearer and louder your kinda like whispering
+kim castillejo I think you'll find the audio has greatly improved on my newer videos. Volume knob is all I got for ya for this one.
+Engineering Explained I think this video deserves a remake. Just saying. I love your work btw!
I would assume the reasoning is that drag cars typically have large engines, and large engines are low revving (relative to smaller engines) so pushrods do the trick at low rpms. Also the oil you use with pushrods is a lot more lenient.
Standing by to see people swapping out their LS motors for an ohc 4 cylinder to go faster, lmfao. Hate on pushrod all you want, I'll be keeping an eye on you in the rear view as you keep talking about hp/liter, and pretend area under the curve doesn't exist. Real world results > theorycrafting, every damn time.
Jeff Smith a 2jz will still make more power than any ls motor and its only like 3 liters so swapping out your ls for a dohc 2jzgte would definitely be better😂😂
@@Tonka470 actually not true. There are companies making 4v ls engines.
The fact is per cubic inch DOHC engines beat ohv for power output, size that ohv engine up to the same size as the ohv and it will absolutely make more power. Apparently the LT5 ZR1 us some thing gm fanboys like to ignore.
@@armymatt83 read up on the Jesel Equal 8...Clean sheet 427, 1 cam 12,000 rpms 1350 hp!
@@vernonknight8611 you're talking about a racing engine first of all not a production engine, secondly if that engine used the same bore and stroke but was dohc it would make more power. You can't get around the physics.
Yeah they're a solid company. Took that picture in Maranello when I went to visit the homeland of Ferrari. Quite a town.
There is another cam lobe behind (think into the whiteboard) the first lobe which operates the exhaust valve for that particular cylinder, with the lobe in front on it (on the camshaft) operating the intake valve.
This is my favorite video bro, it's such a vibe to listen and learn with someone as chill as you, high tides brahh
Sure it's possible, the 5.0 in the Mustang is doing it. I just mention that one because it's common, plenty of V's use DOHC and have for a while. More complicated? Perhaps, but the Mustang's redline tells you it comes with benefit!
Yeah but at the cost of low end torque...the question is which will last longer pushrod or dohc
@@MARTPEREfor the sake of racing and performance. Hp matters more than torque for racing. That engine is geared more towards racing than, street. This is self evident in drag cars which have really "peaky engines" with relatively low torque and insane hp numbers.
@@josuegarcia-tj8ocgreat example would be Hemi vs Coyotes…one made for drag racing & one made for the track💯
Thank you for taking the time to make these videos, they are so educational and easy to follow and understand.Fitz
Quad-cam means it's a V block (or other block where the cylinders are separated) and each set of cylinders have DOHC. 2 + 2 = 4 cams total.
watching a 2011 vid in 2018.. you've come a long way!
if this guy had the budget/time to produce 3d models in his vids, he would be hitting millions of views. still great stuff, keep it up!
really have to give thumbs up, great explanation! I deal in small engines, mostly antique flathead and am building my knowledge about all different kinds. Ofc, things like dual cam are generally not applicable for them, but still appreciate getting to learn about engines in general 👍
Good on ya mate. It's good to see people with auto mechanical knowledge do not always need to smoke a pipe, nearing retirement with black fingers and mountains of facial hair. Congrats for youtube partner acceptance. Clear presentation.
All the best, Mark. UK
Many of them likely are, for simplicity and compactness.
Right, but the reason is that it's much easier to push air out than it is to pull air in. A closing cylinder (piston moving up) the air must escape. As the piston moves down on intake, a partial vacuum is created, and this pulls in the air, which isn't as easy of a task.
Well, essentially this happens regardless of the cam design, but two cams allows for more tweaking of the timing. And when you say "pulled" it's simply the valve spring pushing the valve closed.
wow...8 years later...you have evolved. great success 2M subs later
Dual overhead cams, as discussed in the video, with variable valve timing (ability to alter the valve timing).
I've got the OHV 4.0liter V6 by Ford in in my '98 4x4 Explorer. 250,000+ miles and still running strong. I typically use Castrol GTX 20W50 + Lucas oil. You can hear a lifter on start ups or a loose timing tensioner but the motor does not give up. It still produces great power and throttle response. Built Ford Tough. -TX
There are only more springs if there are more valves, and more valves means better airflow. The greater the area that air is allowed to come in, the easier (and greater amount of air) it is for the air to come in. Better airflow = more power with the same engine, meaning the engine is more efficient at producing power. Yes, the effects will be noticed more at higher rpm, but that doesn't change the principle.
Very similar to the V pushrod diagram I have shown, only remove one of the cylinder banks.
@joeslimon True, but this depends on the layout as well. A dohc boxer engine will have a lower center of gravity than a "V" pushrod engine.
I find this very good and informing . I thought I new about these things ,but not this clear in my mind how each one workedThank you so much , mr clever
finaly i find a good example one dude had almost the same title and was speaking korean ... thanks man!
you have a brilliantly clear way of explaining things - absolutely great
I'm a fan of small, powerful, and efficient engines. Emphasis on efficient. If it can be done with less weight and less volume, power to it. That said, there are some inherent reliability benefits of a high volume relatively low powered engine.
It allows you to control the intake valves separately from the exhaust valves.
You're welcome!
Dude, pretty good vid for dummies. Well done.
Great video man, this helped out quite a bit. Very easy to understand and follow, good production quality and visual aids. thanks!
Dude your the best, I've worked on cars and study cars (in particular my car) and you've helped a lot. Given me a lot to inspire to lol thanks
One of the best channels in TH-cam. Thank You!
Powerful words, thank you!!
Who are you replying to? I've seen this kind of thing before on TH-cam comments. Is it because back in the day, TH-cam didn't have a "reply" function for comments, so you had to just leave a comment directed at someone and hope they know who you're talking to? This interests me.
I was bored in the beginning, but as you advanced, it became interesting. Also worth mentioning is that if you want a smooth ride at higher RPMs , you'd rather go with OHC instead of an OHV. an example is Lexus, which uses DOHC in its V8s and doesn't have to increase the wheelbase in its cars to get a smoother ride it's known for
They have 2 cams, one on each side, but it's still considered sohc because a single cam is controlling the valves for each cylinder bank.
@ThunderViktor As long as you find something that fits, I see no problem. I actually had a friend with a 2000 Focus who also had to replace the engine. I'm not sure what engine you plan on replacing it with, but DOHC is the modern valvetrain style.