Very cool. I’m a heavy duty mechanic who works on locomotives for a major railway. Best thing is thanks to the way the locomotives are built, they have a dyno built into them similar to how your chassis dyno works electrically. After each repair, we get to take these 4500 horsepower monsters and get to load test them at their 4500 hp rated full load for literal hours. It’s awesome.
It’s cool if you’re actually the maintenance dude at some road side historical society that has one of those mini train rides for kids and you’re just using an insane correction factor. You can just say it.
@@speed150mph mmmmm, big diesel gensets :) friend did his sparky apprentice doing backup generators... same idea. just short it out and ramp up the field windings... thats the dyno right there. unfortunately... wheres the heat develop? can only do it for a few seconds... im guessing you guys just use the train itself... i got a big gripe at the moment about people using BLDCs as generators... things like jacobs law and how generators even work. wheres the HEAT? wheres the work being done? "i made 24 volts! yaaaay!" how much load was the generator imposing? what did it take to spin? whats the power? whats the efficiency? generators are a little bit more involved than waving magnets past wires... but not really? just takes a little... thinking of things. connect the dots. the shame about so called modern education is how it generalises so much, and has a lot of things being explained by people that have no idea how anything works themselves! jacobs law being an example. knew the principle my whole life. never had a name for it. its just newtons law really. 1/2mv2. action, reaction. but its a fundamental, so simple to understand, yet its never dwelt upon in any electrical theory ive been taught? impedance matching, wound OPTs before, had another brush-up recently getting into induction heaters... but never much talk of how the source and the load are so intimately related! i had to go hunting for the term, i knew it had a name...
@@paradiselost9946 our locomotives have what’s called dynamic breaks. Essentially what they do it take the big electric drive motors, turn them into generators, and route that power to large resistor grids in order to slow down the train without using the brake shoes. In order to dyno the locomotive engine, we take the power from the main alternator and direct it to the resistor grids.
@@speed150mph forgot about them resistors and the braking. still, same deal applies. cant go lower in resistance than the generators winding resistance itself, and when its equal, same amount of heat dumped in the resistor is dumped in the windings. shorting it out... all in the windings. only so much load you can apply to the generator with a resistor for so long before it burns out. all that power overcoming lenz reactions has to appear somewhere as something. trains gotta keep the voltages and currents within the limits of the generator itself. shorting at those power levels tends to make windings shred themselves and large moving chunks of iron get airborne... lol, got B&W photos of turbogenerators shorted out... messy. youre probably aware of the sort of forces present on the windings of a generator at that size? resistors are easier. yeah, i remember them now... big roof mounted things. eddy current brake just does away with the wires and resistors altogether. lot more robust. main issue is cooling the conductor... all that power is appearing as heat in a rather small area. not really suited to trains at all... but fine on a truck. made one years ago with a 6mm copper plate between solenoids. about 50kw and yeah... cooling issues. people forget an average bar heater is only 2kw...
GREAT video. Not only is the production quality solid, the agenda was really on point. I don't believe there was a single piece of fluff. I got 20 minutes of value out of a 20 minute video. This is how it should be.
I’m a Subaru guy but I like to learn. I came into this really only interested in what you had to say about correction. The shops in Colorado Springs give out.. you won’t believe this.. 20% corrections. It’s freakin’ nuts. I’ve got the sheets to prove it. The shop I go to though goes by what you’ve said. They give out no correction because of our altitude. These poor kids getting ripped off it’s nuts. Thanks for the video.
But dynos are just that comparisons, only like for like on the same dyno, Mustang and the Aussie dynos are the heart breakers… though both can be setup to read high.
In their defense, if some Subaru kid is paying you $250-600 to dyno his WRX and the car puts 160hp to wheel at 6000' on a 90*F day he's not going to tell any of his buddies to go to that Dyno shop. But if you show him a sheet with 200hp wheel and 240hp crank the customer will feel a lot better about their results.
There are a few things that should be considered before you start the upgrade that will require looking at dyno results. This is partly based on what a guy who made dragster engines told me: 1) Always fix only real problems. It is best to write down what the issue in use is that you need to solve. You then need to make your plan to solve that. If the thing is a truck that has to tow up a mountain the issue is a lot different than if you are going 1/4 miles. 2) Every percentage you increase horse power by, you also increased the need for cooling by. You may want to upgrade cooling before you upgrade horse power so you are ready for the needed cooling. Check before you start. 3) If you are towing, is your electrical system up to what you need? If electrical needs to be upgraded, you are best off to plan that at the time of other work because the two efforts can partly happen at the same time. 4) Be careful in calling people out for automotive lies. Some people have a lot of their self worth tied up in the vehicle they drive. They may react like you questioned their manhood or the marital status of their parents. It is best to just say "cool" and go on with what you are doing.
I agree with everything except #4. Everyone needs to be called out for their "automotive lies". I don't care what kind of self worth you have tied up in your vehicle or your reaction. Bullshit is bullshit!
@@turbostang92 I think it depends on how there going about it, if it's a little lie that makes them happier, or a self justification of a purchase then it should be treated differently to someone's who's preaching a certain product to others or bragging and trashing on other people. I mean I certainly say my cars factory torque value but know that it's a 15 year old car that doesn't pull that hard anymore for a number of reasons. I don't use it too sell more of a certain product tho and that little white lie would rarely hurt others. But regardless I certainly agree bullshit IS bullshit
@@2Fly4me77 lol, its a bit like my lil nsr150. gotten up to 200km/h, could do more... "theyre speedos are optimistic"... yet the speedo seems accurate at 110 in the general flow of traffic, accurate at 60 in traffic, accurate past speed cameras and the like? so whats the BS? that a lil 150 can actually exceed 200kmh, or that the speedos are "optimistic"? they do have 240 on them...
As a calibration technician and student of Metrology, this is an outstanding video and is very informative. Might be a little complicated for some, but for car nerds like me, this is great.
Fabulous! Great writing (that is first and foremost). Great production values: editing, shot making, pacing. Facts pour out of this episode almost every other second. It is great. I know it took much longer to make than if you were just standing in front of a white board and talking, but you know the strengths and weaknesses of your medium. You played to your strengths and minimized your weaknesses. Well done!
Excellent video! Just a quick note. The equation that is shown only works for Imperial (ft-lb). For metric (NM) instead of 5252, you want to use 7127. This means, in a NM measurement, the HP and TQ curves will intersect at 7127 :)
Gale Banks is a legend. I’m going to support true American diesel enthusiast by up fitting my 2001 Ram with a full banks treatment. Really appreciate the informative videos.
Just to clarify, dynos do not only measure torque. It depends on the dyno design. In fact, your Mustang chassis dyno only measures the horsepower observed at the roller and back-calculates torque via RPM input. Try a pull without an RPM pickup and you’ll still record the same horsepower curve. Even without the PAU and strain gauge, it would still measure horsepower. Albeit, with only inertia load.
16:56 FWIW, since we're on the internet and anyone can watch this, it might be worth mentioning that your equation uses HP (imperial horsepower, about 746 W) for power and pound-feet (lbf.ft) for torque. If you like kilowatts and Newton-meters then the conversion factor is 1/9549, for HP and Nm it's 1/7124, and for PS (metric horsepower, about 736 W) and Nm it's 1/7028.
Engine dyno measure off the crank not flywheel. The Crank man... Engine Dyno Coupling A coupling is a device that links two shafts at their ends so that power can be transmitted. Shaft not disc, therefore measurement is off of a shaft, crank shaft. Great job guys. Really great job. More of these videos are needed for our young generations.
Good stuff, guys. Brings back memories of long days in engine development at Cummins/Onan test cells. Retired engineer, here. Working on a Harley upgrade development these days.
Harley upgrade development... interesting. It's a shame their investment and time with Buell didn't work out. I mean I have a Buell but I feel there was potential there. Good luck with the future of HD.
Thank You! Drag times used to be a good indicator if someone was lying. I remember an NHRDA event where guys with sema looking engine bays and multiple turbos were complaining about low #'s on an available Dyno. The disappointment on their faces was hilarious.
Yes, "SEMA" appearance isn't a recommendation - some will builders will have immaculate bays and the performance to match, but it isn't always the case.
Came here to learn about dynos…10 min 35 seconds, see a flashback to Geneva Steel in Orem Utah. Half the county worked there before it shut down in 2000…It’s now all movie theaters and town houses now. What an unexpected flash back
One of my favorites is when someone hands me a dyno sheet they are really proud of. It's a naturally aspirated engine, and I look over to the right, to see volumetric efficiency between peak torque and hp was over 150%. 🙄
Considering a properly tuned NA engine can reach 130%, that seems only about as suspicious as bad correction factors. But this is also something I know less about than anything else with an engine. So whether or not 130% is a high-ball or low-ball estimate for a properly tuned NA engine.. I do not know!
@@guard13007 If you are getting a real 130% VE, you are the elite of the elite. As installed in chassis, that's not a number I have ever seen with honest testing.
@@guard13007 For a naturally aspirated road car engine I'd be sceptical of anything about 115%. Unless they have special cams, special intake runners and special exhaust manifolds.
The lines may or may not cross at 5252, it depends on how the dyno sheet it set up. It's the NUMBERS (hp and lb ft) that should match at 5252 not necessarily the lines. Often you will see dyno sheets with different scales for tq and hp on opposing sides of the chart, it those case the lines absolutely should not cross. Also, this is all assuming tq is being measured in lb ft. Many Europeans are using NM or something else in which case the lines won't cross at 5252 and the numbers won't there.
Hub dynos will read higher than a roller dyno because there are inertia losses when accelerating the wheels on the roller dyno, but they are not present when attached to the hub dyno.
I have been a fan of Banks products since HS as my dad worked in the RV business. Your products have always been what Banks claimed that they were. Love that you are putting out the information that will make sure that you are the best products on the market.
This reminds me of the false assertion that "Reducing engine rotating mass creates MORE Horsepower". It does NOT. The many examples where they try to "Prove" this using inertia Dynos are perfect examples of cheating. They do a dyno run with the stock engine rotating mass on an inertia Dyno, then they reduce the rotating mass and do the dyno run again showing an increase in HP. The part they do NOT tell you is that the software in the Dyno NEEDS TO KNOW the engine rotating mass. If you DONT update the rotating mass in the software for the second run, then OF COURSE you will see an "increase in HP". This is CHEATING. IF you update the correct engine rotating mass in the software you will see NO CHANGE in HP.
I had an STi that I had built (over 10 years ago now) at a shop that had a Mustang dyno. It was a Stock Turbo E85 car with bolt-ons. Put down 335whp and 375wtq on their Mustang dyno which is actually pretty decent. I went to the track thinking it was going to run at least mid 12's. I barely squeaked out a 13.2 @ 103, flat foot shifting it and with a 1.6 60 foot, so it wasn't a driving issue. DA was in the 1800's too so that wasn't an issue. I posted the dyno graph on an STi forum and someone pointed out that they were using a 1.23 correction factor! So pretty much they were showing crank numbers, lol. Ever since that experience, I take dyno sheets with a grain of salt.
note for european guys expressing power in kW and torque in Nm: the correcting factor is 2*pi/60000, so power in kW = torque in Nm * rpm /9549.3, so if you use the same scale on the y axys the torque curve and power curve meet at 9549.3 rpm, which is unrealistic on the vast majority of engines because they meet the redline way below (my car engine for example redlines around 6000rpm), so in a european dyno sheet the power curve is completely below the torque curve.
Excellent presentation. I've seen engine builders, even on TH-cam, putting engines on their dyno' and running them barely warm, even cold, with electric water pump drives when it'll be installed with an engine driven pump, no fan or other parasitic accessories, open exhausts, no air filters, etc, and saying that's what the power of the engine is. IMO, means SFA - what matters is what the engine produces IN THE CAR, with everything in place! Even worse, they'll 'tune" the engine under those SPECIFIC dyno' conditions and then send the engine to their customers - I've a better chance of winning the LOTTO ten times in a row than they have of getting the " tune" correct for the vehicle. Other tricks are using different tyre pressures and/or running them cold vs hot, using different tyres and/or wheels, etc. Excellent explanation for the 5252 correction factor - so many people parrot it without understanding a thing about it or how it was derived (it's 5252.113112 ... - but it's close enough). The crossover only works when the same scale is used for both torque and power, so if a graph looks funny, first check that. Hmmm, bit of an earth tremor there - some part of the country's been woken up this morning, and after a couple of minutes still some light movement... [edit] No hassles, it was just a 5.something.
Alternate video title: How to test engineer; engine testing PoV. Much of the stuff you bring up, like the basic idea of bringing the 'test item' to a stable state prior to doing any actual measurements is test engineering 101 and can be applied to any testing. Great video.
this video is phenomenal. lots of backyard tuners and builders seem to forget that tons of mechanical engineering knowledge goes into properly measuring torque and power correctly and the differences people see from dyno to dyno are likely the result of a lack of knowledge with no intended malice. the point about observed horsepower is a very good one to make though. I live somewhere that does have a substantial altitude compared to what one would expect an SAE spec dyno test to run and ill likely never see the numbers shown in said SAE test on the road.
I don't know why this was on my YT feed, but I watched it all & it was interesting. It becomes another piece of trivia that I'll probably never use. That 52 52 calculation is easy to remember, as long as I remember how many weeks in a year.
That was very usefull thanks. Recently had my car tuned at a good friends shop. Made around 195HP and good power to 9500. Back home i did some fine tuning and corrections and it made 120hp (exactly stock lol) on my dyno. Reverted all changes back to the 195hp tune and still got 120hp. Wouldnt even want to rev past 8000. Tought my dyno broke and was loading the engine down, but other cars measure correct on mine. Tought he did some tricks but he dyno sheet is legit. IDK anymore
You guys are great at sharing knowledge. I had a foggy idea and could catch a really bad cheater, but now I have a good grasp of all the major deals and math. Keep up the good work.
Hats off to you Erik, and the Banks Team. Great video and I learned a few more things, such as how some skew their numbers. A lot of this is common sense such as repeatability and keeping the inputs as close as possible to get those outputs. Never thought someone would use different atmospheric conditions to show any kind of a difference. I have a Data Logger that I installed with a Pedal Monster, collecting lots of data on my 2021 Ram 6.7 HO, and have a Monster Ram sitting in a box ready to install. You can bet tubes and air box will be next on my list. It will be fun comparing all the data. And yes, I have the rear Dif cover.
What a great video. Dude your presentation skills are awesome. I don’t watch many Banks videos (though I respect the heck out of Mr. banks) but I’m glad I took the time to watch this one.
Large corrections can be useful(IF applied properly. It is done every day in aviation.), but I wouldn't put too much faith in them for comparing the tune of individual vehicle mods from two very different locations. A correction for changes in weather between two runs at the same location and vehicle is very appropriate. A large correction would also acceptable if the two stations have their correction formula cross checked with a reference engine, but this would mostly apply to a manufacturer's quality control of a specific engine design, rather than being suitable for a wide range of vehicles.
I'm glad when I was tuning my big block Mopar on my friends Dyno we found the best tune but most importantly the Dyno gave me the numbers I need for proper gearing and converter stall. That's all a Dyno is, a tool for tuning and stuff like I mentioned.
I had to pause the video when you said gotta dyno cars for hours to say you're right. I had a 1986 Ford Festiva and loved it! I could fit a tile saw in it, or a paint pump. I got nine gallons of gas a week and could park on a sidewalk (don't do that) but it was awesome. Anyway, when you have 90 squirrels turning the wheel in on Portland freeways, you're floored at all times that you're not going five miles an hour in traffic. Sometimes coming back into Portland heading down hill I coulda had 95 squirrels. Bought it for $100, drove it for 20k miles and sold it for $400. $250 in maintenance, made thousands working with it, saved at least a few thousand in fuel and maintenance...best car I've ever had.
Really good video. Another point to consider is that sometimes correction factors should not be applied because the calibration has a torque based model - that is some calibration strategies predict torque and hold it constant for some range of ambient changes, specifically turbo charged engines. It then gets really messy at high altitude as the performance will drop off as turbo speed limits, surge limits compressor out temperature limits are hit and this can not be estimated purely based on the performance seen at one condition.
I always look at 5252 rpm to see that the numbers are the same but I also look at 2626 rpm on Diesels where the hp is 1/2 the torque and on high rpm engines I look at 7878 rpm where hp is 1 .5 times torque. I would like to see the printout on the exotic Aston Martin Valkyrie engine that reportedly puts out about 1000hp at about 10500 rpm which would be 500 ft lbs of torque. Also have noticed the some dyno operators pay some attention to water temp but don't even mention oil temp. I work around high performance boats and have installed oil temp gauges so I can size oil coolers. Started doing this in the early 1970's. A lot of speedboats have oversized oil coolers without oil thermostats and run low oil temperature and some also run low water temperature.
Some Car dealerships will give you an estimate on your trade in value from a poor area where cars aren't selling for much, and then they show the value of thiers from somewhere in California, or maybe New York City
I supercharged my mustang. I had it on the dyno when it was 98% stock (it had a catback) and on the dyno after the lth, supercharger and water meth kit. I don't focus too much on the numbers. I just know the car is way more fun on the street now.
This is an excellent video explaining how horse power can be different if not using correction factors and elements when using a dyno to calculate real horse power. As a heavy-duty mechanic it kills me to see car and motorcycle dyno's just consist of a quick rev up and giving inflated numbers. I worked for Caterpillar for ten years in their engine division. I was par dyno certified. I chassey dyno trucks and engine dyno engines every day. Even though the electronically controlled dyno would calculate the correction factors you had to know how to calculate the correction factors by hand. Knowing all this I could manipulate the horse power readings and fuel rates per hour and Caterpillar generate new "new fuel numbers" for the engines computer. It was a way to secretly get more horse power out of a stock engine especially if it was still under warranty. you could increase the horse power by 25% just with fuel numbers. Using the Wong software could get another 10% of horse power. Using wrong cams, injectors and turbos could add up to 30%
The fun ones are when they don't show the weather readings, and they stick the weather sensor somewhere hot and damp when it isn't, thus artificially inflating the true numbers. I agree the best method is observed power vs corrected when tuning your own car. I'd even say its best when doing a direct comparison of x part vs y part, provided the conditions are similar enough. Also goes to show you that when companies advertise gains over stock, its best to see who else has run the stock one to see if the numbers are skewed.
I destroyed AFE employees online back 8 years ago when they were posting dyno sheets that tq and hp crossed at 4000 rpm. They ended up removing all their dyno sheets online and starting over. Never buy their products
It would be cool to see a “report card” on different auto manufacturers’ honesty about the power their cars make. I’ve heard (but can’t confirm) that Ford tends to “undersell” - dyno testing with regular pump gas and giving real-world numbers, whereas others tend to test in optimal conditions.
Chevy is great about this the LM7 is advertised at 270 to 295 flywheel hp but it actually usually puts that to the rearwheels, so they dont overinflate numbers.
Great video! Makes the whole "dyno mess" a lot easier to understand, and also, why you shouldn't use the "special price for you my friend" type of dyno shops. Last time when Gale talked about your dyno setup, I had a run on the dynos in somewhat close range (within 4 hours drive). Non of them could boost a similar setup. I live in Norway, and temperature/humidity is way off and CF is needed. Most companies I talked to, claimed that was the reason for them to run the dyno indoors and why they needed hood open and basically checked all boxes on "how to catch a cheater" :D
Well even if you have a 100% legit dyno. A other dyno can give you a bit of a fake number. But if it is just your car that you dyno before a modification and later just fine tune it. If the numbers go up and all value is good i think that what the number of the output on the paper is not the big deal. Many people overestimate the numbers what an engine or parts is given. Also even if it can boost the HK/Nm up. In the long run the HK/Nm will drop. this is for temp is rising and the turbo is just pumping hot air. Here in the north. many shops have the dynos inside just for the use of all day. It is easy to have a controlled temp of like 20C. But the temp can be like -20 and + 30. that is a bit to much to just CF of. The next parts is that it is expensive stuff and noise regulations. Or you can have a dyno test without the rear wheels or on the open road. HK/Nm is just a number. Some one is always going to fly away from you on a car that have a different gearbox. not so heavy car. single driver without passenger and so on. Change the wheels and you need to re dyno if you like the number on the paper. I have a B5234T5 that i am going to see what the numbers can be. The shop have dyno quite a lot of that engine or family so even if i can say that my numbers would be around 550-600hk, i think that a 450-500hk is more fare. and even if you have a big number on the end. The car / engine can be very boring to drive on what you are using it fore. I would rather have a ECU map that have power in the "fun part" of the register and not just in the 6000-8000 rpm range. A very fast car can be dead slow on a track where there is no long parts for the engine to use the higher rpm.
That was so much better than I thought it would be. I expected a lame rant about everything always crossing at 5252 RPM. Since you can scale HP and Torque separately on the screen, they can, visually, on a chart, cross at any RPM that you have torque data for. Using real math to check the results, perfect. On a side note, I'm always a little amused then the air filter tests on Dynojet dynos show the run numbers in the screen shot. Something like Run.003 366HP, Run.023 399HP. It took 20 runs to test an air filter? Or was it 20 runs to get the day's max run?
I believe the actual setup of the DYNO can make the numbers higher as well. For instances altertering the weight of the roller will effect the numbers.
well even the expansion of the rubber on the wheel gets a little bigger when hot or in higher rpm s. So the number youget from a dyno is more the number for you self and if you go back when you have upgraded or changed something then you can see if the numbers or curve have changed. the digits on the bottom on the page is more a " fun part".
Onje thing I do like about thw Ford is that in manual mode it will hold whatever gear you are in regardless of rpm or throttle position. You can lug it full throttle in 6th gear at 30mph at 1100rpm and it will not downshift. So if you really want to use thw available torque down low you can.
i learnt all my stuff from steam, so there was another one, indicated horsepower... the pressure in the cylinder over time. shows efficiency of the engine itself. the crank, the eccentrics... so much potential in the pressure, but only so much makes it out as actual brake horsepower, flywheel power... (not going to make this long, but imho, if the ICE is to progress, we have to overcome the inherent mechanical disadvantage of the crankshaft being at TDC when the maximum pressure is being applied to the piston... it has to act tangentially at TDC, not radially. ideally tangential for the full duration of expansion. figure THAT one out, and the entire nature of the ICE as we know it will change... as it is, the ICE is a glorified steam engine with spark plugs, an air compressor that drives itself with a little bit of output on the side. petrolhead my whole life and i HATE THE DAMN THINGS! anyway... end digression.) sweep time is highly under-rated... and its critical for carbs. it gets into the emulsion tube side of things... EFI just masks all the issues out as its main intention is deliver optimum fuel for any condition... at a fixed throttle setting, air speed through the venturi is based on RPM alone. the suction on the jet is determined by the air speed. as RPM increases, air speed increases, jet suction increases, and the mixture gets richer and richer. the suction on the jet rises at a square? cube? its a non-linear curve, air speed to suction. vacuum. pressure differential. sigh... terminology matters! emulsion tubes allow progressively more and more air leak into the main jet and lean the mixture out, make it ideally linear with air speed and RPM. or closer to what the engine demands, anyway. as you get higher and higher power levels it gets harder and harder to try and tune this... on a cruddy little 5hp engine gokart, barely accelerating... you can FEEL the emulsion tube as you accelerate... start playing around with the holes and you really start to notice! flat spots and bog through the RPM range on one throttle setting. and as no-one really understands emulsion tubes at all, they start changing jets and needles and clips (im a motorbike guy...) instead and forever chase their tails... bikes are particularly fun as they have such a wide RPM range, and CV carbs are just another level of mindfukkery... youre trying to isolate several overlapping and interacting circuits but arent even made aware of one of the fundamental ones, how emulsion tubes work. yeah, i made a dyno. eddy currents rule. conductor (6mm copper plate) magnetic field. easy. you didnt mention how fast they heat up! im limited to about 100kw simply due to heat... that is a LOT to get rid of. and to think, the engine is actually throwing away another 300KW or so... like, a standard heater is only 2.4KW!
That simple relationship doesn't apply to combustion engines, or more specifically it does but not the way it might seem - it's the downward torque on the piston. The power is directly related to the conversion of chemical energy, which determines the downward force on the piston. But the torque determines on the leverage the piston has on the crankshaft, which is by definition half the stroke length at its peak (at 90˚). The stroke length creates a relationship between rpm, torque, and power (or force). The simple relationship is the torque of the _piston_ , but this is then geared through the piston shaft onto the crankshaft. It DOES apply to electrical engines, where it is the relationship between electrical power (minus losses) and torque. In addition, engine timing optimized for power is optimized for _airflow_ , and hence maximizes intake and exhaust valves open times, power is then created by running higher rpms (more combustion cycles = more fuel chemical energy released per second = more power), whole torque is optimized by keeping valves _closed_ to maximize the time the downward force can act on the piston. This leaves less open time, and as rpms go up the mechanical tolerances makes it impossible to maintain the short open angles, and so puts a limit on the rpm sustainable and hence peak power. A longer stroke also means the piston has to travel faster at the same rpm, due to the implicit gearing.
I have run and tuned bikes on five different DJ chassis dynos (over *17,000 dyno runs* logged) so I can confirm what's been said here. 1: making pulls before completely warming EVERYTHING up does make a difference. 2: doing pulls in different gears makes a difference and 3: using load control during pulls (longer sweep, slower roll-on rate) for sure makes a difference with both "proper tuning" and HP numbers. But I'm also adding that the *TIRES* used can/do make a difference as well. I've done back to back testing several times over the years (swapping identical wheels with different tires mounted on them = less than 10 minutes between test pulls). The OEM tires always show the highest numbers while most Drag Radials on bikes "rob" somewhere between 9-12Hp and (not kidding) Drag Slicks rob 15-20+Hp (with data confirming there was no tire spin/slippage on any of the tires tested). But since everything about racing is give and take, the added traction (when needed) far out weighs the loss of power... And lastly (my experience with slower roll-on rates). What surprised me the most is, simply adding a few % of duty cycle to the Eddy Brake (longer sweep time) makes a 20Hp difference =10% on 200 RWHP bikes...
Great info, I still have a question. Chassis dyno measures the torque at the wheel, we know the resistance of the dyno roller and hence the torque at the wheel. Torque at the engine flywheel (all dyno charts are made to look like they come from engine RPM) would still need to be calculated using current gear ratio, differential ratio and the ratio of dyno rolller diameter to wheel diameter, correct?
We have ONE shop in my area this thorough and I appreciate them. They just moved into a facility twice the size of their old one so I'm sure everyone else does too.
I caught a local performance tuner fudging the numbers on my built 2012 EVO MR. I used their service since my friend's shop was booked out 4 months. I bribed my friend with beer and we dyno'd my car after hours...there was a 20% difference. Same model and type of dyno. Same type of runs. Same tank of gas. etc.
19:23 your dotted line power curve doesn't cross the torque curve at the same place. I'm wondering how you can get the standard atmosphere humidity at zero percent. It gets into the single digits around here sometimes but zero seems impossible.
So does the vehicle weight that's input into a Mustang dyno skew results? My original tuner had my car in at 3800lbs when I'm actually 4200lbs. What about all the other factors like friction coefficients, drag, frontal area, etc? Great video.
There is some good information here, but most chassis dynos don't measure torque. They measure hp and then calculate the torque based on what rpm the hp was achieved.
I tested my 03 Cobra on two types of dynos when 100% stock. An eddy current Mustang dyno and a Dynojet. Both were at sea level, but temps were about 20 degrees colder when on the Mustang. On it, the Mustang I made 355 hp on the Dynojet it made 372 hp which I thought was interesting.
Dynojets are generally acceleration dynos that measure horse power and back calculate torque where as Mustang is a loading dyno that measures torque and calculates HP. Say you put heavy wheels on the car, this will slow 1/4 mile times due to the added inertia and will lower acceleration dyno results but will have minimal to no effect on a loading dynos results.
I caught this with Cleetus McFarland recently. I think it was done out of ignorance rather than purposefully, but they dyno’d they’re giveaway 10 speed F-150 in 4th gear instead of 7th. Seemed wrong to me at the time to still be in 4th, now I know I was correct. Although there were more losses in the run, I think it showed more horsepower due to the uneven ratio
Yes and no. It gets to a higher viscosity rating, but that rating is based on a test performed at a set temperature. So a 5w-30 oil acts like a 5 when cold and a 30 when hot**, but a hot 30 is still thinner than a cold 5. Try heating up some 20w-50 on the stove to 200 degrees and see how it pors compared to 0w-20 out of the bottle. The multi-weight is there to reduce the thinning effect of heat, but they can't reverse it. ** The description above will get you the understanding, but I did lie slightly. When I compared a cold 5 to a hot 30, those numbers are not exactly equivalent. So like on a 5w-30, that 5 is based on one test and the 30 is based on a totally different test. Gear lubes and other oils all have their own different tests, too. So you know that 5w-XX motor oil is thinner from cold than a 20w-XX, but that 20w is not actually equivalent to the hot rating of an XX-20 oil. It IS still true that a hot 30 is thinner than a cold 5w, which you can verify with 5w-30 on the stove, but just know that those numbers aren't directly comparable to each other.
@@NumbByDawn The different tests definitely make things confusing, but there's a reason they do it that way. Each test is optimized to score the performance of the oil in the environment that the number is trying to tell us about. So the 5w number in 5w-30 is tested cold and the 30 is tested hot, and those numbers are based on some imaginary fluid devised for the testing standard. If you took a straight 40wt oil (which means it scores a 40 in the hot test), and ran that through the cold test, it probably wouldn't score a 40w. If you took 5 different straight 40 oils, they'd probably all get different cold test numbers, because lots of things affect how these oils change with temperature, and motor oil has a lot of stuff in it. If the numbers represented the same thing, it HAS to mean that either the test or the oil is the same. Having different tests gives more relevant information, but it's just not as clear. The difference between the w and second number is not THAT big, though. It's just the correction factor. Now, where things really get funny is when you compare different kinds of fluids. Those tests are TOTALLY different, and the numbers mean nothing relative to each other. For example, 20w-50 motor oil is slightly thicker than 75w-90 gear lube.
Just like testing a cold air intake with the hood up there are a lot of companies that do that but they think most people don't know exactly what they are looking at. GREAT VIDEO and Banks is one of the best companies not only for their parts they call out other companies 💩
Okay, I've aways wondered where the 5252 constant came from. This got me mostly there. I am curious how the chassis dyno compensates for the diff gear ratio and the tire size. Are those variables the operator has to input? Because it seems like the diff gears would be a torque multiplier while a bigger tire takes more torque to turn.
Last time I read a dyno spec I'm sure it said any correction factor not to exceed 5% in total and not to be applied to anything that uses forced induction.
My MR2 has a side mounted intercooler and intake. Do dyno shops properly put fans at all important areas? Also...if a fan is mounted by the intercooler, is it blowing from the side or like a real world condition as lateral air flow? Good info on the rest of the video.
Hopefully this vid gets more hits as Banks has always been a no fluff straight shooter just the facts kind've guy: cudo's to him and his employees. Thanks for saying your dyno only reads "Torque". Most ppl dont understand what the Horsepower phenomenon actually represents and will say grossly misunderstood things like, "Its HP that wins races"! HP is a dimensionless unit and cant exist without Displacement, RPM, and being tied in to the TQ/HP equation. HP is a qualifier of how effectively, (efficiently),TQ is being applied at a per minute per second time frequency. Not only is it a measurement within a time frequency but also a qualification of the 4 Cycle Engine; as in 4 Strokes, specifically the Combustion Cycle. HP is metaphorically qualifying how many times a hammer (Combustion Cycle) hits the anvil (Moment of Force) per minute. Technically ppl should say, "Its the Increase of the application of Torque at a specific RPM that wins races"; but thats too complicated for most, and bragging about HP is more fun. Because the Crank turns twice per one revolution of the Cam, we are dealing with 720° of crank rotation: all these #'s are inter'related. James Watt gave us the standardization of 1 HP per minute of 33,000 and 550 HP per second but never qualified the Power, at least not publically. Funny enough, because the brewary's draft horses turned a grinding stone in a 12 foot circle, RPM was actually qualified at 2.4 rotations per minute; however that was never pursued. James Watt did however utilize a Pressure Wave graph on his steam engines privately in the late 1600's but never applied for Royalties from the King or Engineering Guilds of the day; he kept his Pressure Wave graph tech secret. It took another 60 to 100 years before Pressure Wave tech was being taught by the Engineering Guilds. Until a person understands Radians they will never understand why the use of Pi, RPM's or why the 33,000 variable magically changes to 5252 in the TQ/HP equation. You touched on it when addressing Circular Functions of Rotational Velocity but didnt go too deep in explaining; this is already a 20 minute vid so theres only so far you can go. Afterall, its the individuals responsibility to educate themselves. Very quickly, a circle, (the flywheel), is 360° per 1 rotation. Take any size circle and half of that circle's circumpherance is 180° angle travel, or half a circle. 1/2 a circle is 1 Pi as in 3.14159in Radians. A whole circle is 360° or 2 Pi, as in 2 x Pi, as in 6.283 as in 1 Radian. Take RPM which is Revolutions Per Minute and apply that to James Watts 33,000 ft/lbs per minute and you get, 33,000 ÷ (2xPi) 33,000 ÷ (2 x 3.14159) = 5252.11 There's your 5252 variable You could use James Watt's 550 HP per second but then you would have to divide 60 into 2Pi. The 60 represents 60 seconds per minute while 2Pi represents Radian Velocity of one Revolution. 2Pi ÷ 60 = .104716 (Radians Per Second) Now divide that number into James Watt's 550 HP per second and, 550 ÷ .104716 = 5252.30 Now to get from the Imperial Tq/Hp numbers to the UK's NM power dyno graph simply multiply conversion factor 1.8181 by the 5252 variable 5252 × 1.8181 = 9548.66 Why does this 5252 variable work. Break down the math and you get 2Pi (Radians) per 1 Revolution, Rev's per minute, and 60 seconds per 1 minute. Simply put, Rev's ÷ Seconds ÷ Radians, written as, (38 ÷ 1) × (1 ÷ 60) x (2Pi ÷ 1), the 1's will cancel out, the 2 and 60 are minimized cleaning up the equation as (38 ÷ 30) x 3.14159 = 3.979 Radians per second. Now there's a little history behind the TQ/HP equation. I could go on but this is long enough already. Thx for making your vid PS: I've been watching Banks stuff since the late 80's, always good stuff
Very interesting. From a tuning perspective, could you give a run down on how changes to those things might effect different parameters that are being measured? Say we are trying to do an IM240 or an RG240 test (Repair grade? I think it’s called) to confirm emissions compliance. Are we likely to get different results or would it be possible for someone to cook the results, leading to either a pass or a fail?
5:40 if sweep time is short and engine rapidly accelerates, there are loss of acceleration of intaked air,( and all mass )-for ex when i accelerate in 2. gear usually happens lean mixture, because my lpg system is not dimensioned for that flow rate but when accelerate in 3. or 4. gear at same rpm , no problem, so at rapid acceleration, must accelerate at high rate so in intake is more resistance than if it accelerates slowly
Can you guys do a video explaining how pulling force works? Im an engineer and when i see peoples comments on a video of an f150 lightning pulling a one million pound train then asking how they found a rope that can hold a million pounds it just boggles my mind. Most people don't realize that the straight line pull force from their truck is less than what their truck weighs. Along with that, it'd be great to show how much the coefficient of friction changes when you start spinning your tires. You guys seem like the only ones who could explain this well enough to make everyone understand.
A Toyota pickup pulled the space shuttle over a bridge while the SS was being moved to a museum. Be sure to note that a 1 M LB rope was not needed as rolling force for a wheeled vehicle in good condition is going to be less than it's weight / mass. The key to moving a very heavy object is a slow change in velocity so as not to exceed available friction.
You could probably find discussions on that in tow truck related channels. Also take a look at climbing gear. It gets rated by force, not weight. It ends up being kind of the HP vs torque discussion. You can move something on wheels that weighs a million pounds if you keep the acceleration low. A few hundred pounds of force should move that train. Steel wheels on steel rails keep rolling resistance down vs pneumatic tires.
@@immikeurnot I'm well aware of the physics behind it and can show the math to support it but unfortunately a comment isn't quite as impactful as a well done video by a respected company.
Very cool. I’m a heavy duty mechanic who works on locomotives for a major railway. Best thing is thanks to the way the locomotives are built, they have a dyno built into them similar to how your chassis dyno works electrically. After each repair, we get to take these 4500 horsepower monsters and get to load test them at their 4500 hp rated full load for literal hours. It’s awesome.
It’s cool if you’re actually the maintenance dude at some road side historical society that has one of those mini train rides for kids and you’re just using an insane correction factor. You can just say it.
@@zomblake haha I wish. That sounds more like fun and less like work 🤣
@@speed150mph mmmmm, big diesel gensets :)
friend did his sparky apprentice doing backup generators... same idea. just short it out and ramp up the field windings... thats the dyno right there. unfortunately... wheres the heat develop? can only do it for a few seconds... im guessing you guys just use the train itself...
i got a big gripe at the moment about people using BLDCs as generators... things like jacobs law and how generators even work. wheres the HEAT? wheres the work being done? "i made 24 volts! yaaaay!"
how much load was the generator imposing? what did it take to spin? whats the power? whats the efficiency?
generators are a little bit more involved than waving magnets past wires... but not really? just takes a little... thinking of things. connect the dots.
the shame about so called modern education is how it generalises so much, and has a lot of things being explained by people that have no idea how anything works themselves!
jacobs law being an example. knew the principle my whole life. never had a name for it. its just newtons law really. 1/2mv2. action, reaction. but its a fundamental, so simple to understand, yet its never dwelt upon in any electrical theory ive been taught? impedance matching, wound OPTs before, had another brush-up recently getting into induction heaters... but never much talk of how the source and the load are so intimately related! i had to go hunting for the term, i knew it had a name...
@@paradiselost9946 our locomotives have what’s called dynamic breaks. Essentially what they do it take the big electric drive motors, turn them into generators, and route that power to large resistor grids in order to slow down the train without using the brake shoes. In order to dyno the locomotive engine, we take the power from the main alternator and direct it to the resistor grids.
@@speed150mph forgot about them resistors and the braking. still, same deal applies. cant go lower in resistance than the generators winding resistance itself, and when its equal, same amount of heat dumped in the resistor is dumped in the windings. shorting it out... all in the windings.
only so much load you can apply to the generator with a resistor for so long before it burns out. all that power overcoming lenz reactions has to appear somewhere as something.
trains gotta keep the voltages and currents within the limits of the generator itself. shorting at those power levels tends to make windings shred themselves and large moving chunks of iron get airborne... lol, got B&W photos of turbogenerators shorted out... messy. youre probably aware of the sort of forces present on the windings of a generator at that size?
resistors are easier. yeah, i remember them now... big roof mounted things.
eddy current brake just does away with the wires and resistors altogether. lot more robust. main issue is cooling the conductor... all that power is appearing as heat in a rather small area. not really suited to trains at all... but fine on a truck.
made one years ago with a 6mm copper plate between solenoids. about 50kw and yeah... cooling issues. people forget an average bar heater is only 2kw...
The guys at Banks really know what's up. Teaching me more about dynos than hours worth of videos I've watched in the past.
GREAT video. Not only is the production quality solid, the agenda was really on point. I don't believe there was a single piece of fluff. I got 20 minutes of value out of a 20 minute video. This is how it should be.
I’m a Subaru guy but I like to learn. I came into this really only interested in what you had to say about correction. The shops in Colorado Springs give out.. you won’t believe this.. 20% corrections. It’s freakin’ nuts. I’ve got the sheets to prove it. The shop I go to though goes by what you’ve said. They give out no correction because of our altitude. These poor kids getting ripped off it’s nuts. Thanks for the video.
I just left Colorado Springs the other day to beat the I25N shutdown. I move trucks out of Auto Truck on East Platte.
But dynos are just that comparisons, only like for like on the same dyno, Mustang and the Aussie dynos are the heart breakers… though both can be setup to read high.
@@wobblysauce Maybe you didn’t catch that you should just go off of what the dyno reads rather than just slapping a correction on it
@@wobblysauce what I mean by that is it’s not about if they read high it’s about the correction
In their defense, if some Subaru kid is paying you $250-600 to dyno his WRX and the car puts 160hp to wheel at 6000' on a 90*F day he's not going to tell any of his buddies to go to that Dyno shop. But if you show him a sheet with 200hp wheel and 240hp crank the customer will feel a lot better about their results.
A series on Tuning education is something i would absolutely tune into
If you look on TH-cam for HP academy they show you what it takes to tune a diesel. Hope that helps.
@@TD5rage How has that channel gone over my head for so long!? Great find dude, thanks. 👍
@@RandomlnternetGuy no problem. Glad to help 👍
I see what you did there 👀
@@sandasturner9529 😄
There are a few things that should be considered before you start the upgrade that will require looking at dyno results. This is partly based on what a guy who made dragster engines told me:
1) Always fix only real problems. It is best to write down what the issue in use is that you need to solve. You then need to make your plan to solve that. If the thing is a truck that has to tow up a mountain the issue is a lot different than if you are going 1/4 miles.
2) Every percentage you increase horse power by, you also increased the need for cooling by. You may want to upgrade cooling before you upgrade horse power so you are ready for the needed cooling. Check before you start.
3) If you are towing, is your electrical system up to what you need? If electrical needs to be upgraded, you are best off to plan that at the time of other work because the two efforts can partly happen at the same time.
4) Be careful in calling people out for automotive lies. Some people have a lot of their self worth tied up in the vehicle they drive. They may react like you questioned their manhood or the marital status of their parents. It is best to just say "cool" and go on with what you are doing.
I agree with everything except #4. Everyone needs to be called out for their "automotive lies". I don't care what kind of self worth you have tied up in your vehicle or your reaction. Bullshit is bullshit!
@@turbostang92 I think it depends on how there going about it, if it's a little lie that makes them happier, or a self justification of a purchase then it should be treated differently to someone's who's preaching a certain product to others or bragging and trashing on other people. I mean I certainly say my cars factory torque value but know that it's a 15 year old car that doesn't pull that hard anymore for a number of reasons. I don't use it too sell more of a certain product tho and that little white lie would rarely hurt others.
But regardless I certainly agree bullshit IS bullshit
@@2Fly4me77 lol, its a bit like my lil nsr150.
gotten up to 200km/h, could do more...
"theyre speedos are optimistic"...
yet the speedo seems accurate at 110 in the general flow of traffic, accurate at 60 in traffic, accurate past speed cameras and the like?
so whats the BS? that a lil 150 can actually exceed 200kmh, or that the speedos are "optimistic"?
they do have 240 on them...
As a calibration technician and student of Metrology, this is an outstanding video and is very informative. Might be a little complicated for some, but for car nerds like me, this is great.
Thank you for the compliments!
Me too.
Regards from Brazil!!
Great explanation Erik! The reason I love Banks; data, real data. Only someone with real data and nothing to hide will tell you how to spot fake data.
Fabulous! Great writing (that is first and foremost). Great production values: editing, shot making, pacing. Facts pour out of this episode almost every other second. It is great. I know it took much longer to make than if you were just standing in front of a white board and talking, but you know the strengths and weaknesses of your medium. You played to your strengths and minimized your weaknesses. Well done!
Excellent video! Just a quick note. The equation that is shown only works for Imperial (ft-lb). For metric (NM) instead of 5252, you want to use 7127. This means, in a NM measurement, the HP and TQ curves will intersect at 7127 :)
@@bigboreracing356 Freedom units
thanks
🤮
Gale Banks is a legend. I’m going to support true American diesel enthusiast by up fitting my 2001 Ram with a full banks treatment. Really appreciate the informative videos.
Lol sure.
@@maddoxinc1642 ROFL!!
Hahaha good luck
i've learned so much on this channel. it must be one of the most information dense channels on youtube
Just to clarify, dynos do not only measure torque. It depends on the dyno design. In fact, your Mustang chassis dyno only measures the horsepower observed at the roller and back-calculates torque via RPM input. Try a pull without an RPM pickup and you’ll still record the same horsepower curve. Even without the PAU and strain gauge, it would still measure horsepower. Albeit, with only inertia load.
16:56 FWIW, since we're on the internet and anyone can watch this, it might be worth mentioning that your equation uses HP (imperial horsepower, about 746 W) for power and pound-feet (lbf.ft) for torque. If you like kilowatts and Newton-meters then the conversion factor is 1/9549, for HP and Nm it's 1/7124, and for PS (metric horsepower, about 736 W) and Nm it's 1/7028.
Engine dyno measure off the crank not flywheel. The Crank man...
Engine Dyno Coupling
A coupling is a device that links two shafts at their ends so that power can be transmitted.
Shaft not disc, therefore measurement is off of a shaft, crank shaft.
Great job guys. Really great job. More of these videos are needed for our young generations.
You make a good point. Thanks for the keen eye.
Good stuff, guys. Brings back memories of long days in engine development at Cummins/Onan test cells. Retired engineer, here. Working on a Harley upgrade development these days.
Harley upgrade development... interesting. It's a shame their investment and time with Buell didn't work out. I mean I have a Buell but I feel there was potential there. Good luck with the future of HD.
Thank You! Drag times used to be a good indicator if someone was lying. I remember an NHRDA event where guys with sema looking engine bays and multiple turbos were complaining about low #'s on an available Dyno. The disappointment on their faces was hilarious.
Yes, "SEMA" appearance isn't a recommendation - some will builders will have immaculate bays and the performance to match, but it isn't always the case.
Came here to learn about dynos…10 min 35 seconds, see a flashback to Geneva Steel in Orem Utah. Half the county worked there before it shut down in 2000…It’s now all movie theaters and town houses now. What an unexpected flash back
One of my favorites is when someone hands me a dyno sheet they are really proud of. It's a naturally aspirated engine, and I look over to the right, to see volumetric efficiency between peak torque and hp was over 150%. 🙄
Considering a properly tuned NA engine can reach 130%, that seems only about as suspicious as bad correction factors.
But this is also something I know less about than anything else with an engine. So whether or not 130% is a high-ball or low-ball estimate for a properly tuned NA engine.. I do not know!
@@guard13007 If you are getting a real 130% VE, you are the elite of the elite. As installed in chassis, that's not a number I have ever seen with honest testing.
@@guard13007 For a naturally aspirated road car engine I'd be sceptical of anything about 115%. Unless they have special cams, special intake runners and special exhaust manifolds.
Where/how do you find the VE from a dyno sheet? 🤔
@@dickard8275 Not always listed, but often one of the columns of data is VE.
The lines may or may not cross at 5252, it depends on how the dyno sheet it set up. It's the NUMBERS (hp and lb ft) that should match at 5252 not necessarily the lines. Often you will see dyno sheets with different scales for tq and hp on opposing sides of the chart, it those case the lines absolutely should not cross. Also, this is all assuming tq is being measured in lb ft. Many Europeans are using NM or something else in which case the lines won't cross at 5252 and the numbers won't there.
Exactly, we'r using Nm for the torque measurement, do you know what is the equivalent in Nm to 5252 (lb-ft) ?
@@guillaumeberat5280 for Nm and HP it's 7025 and for Nm and kW it's 9554
@@Supra2JZLife thanks for answering !
Most of the Australian dynos have now gone to hub dyno to prevent wheel slip, variation in tyre size and other things tuners can falsify numbers from.
Hub dynos will read higher than a roller dyno because there are inertia losses when accelerating the wheels on the roller dyno, but they are not present when attached to the hub dyno.
@@a.melburn Donut Media when testing the Miata build did the hub dyno
I can't say the content is exhilarating but Erik did a fine job. Pleasant to watch.
Someone speaks the unspoken... love it. Dyno cheaters are far more common on you-tube then anywhere else.
I have been a fan of Banks products since HS as my dad worked in the RV business. Your products have always been what Banks claimed that they were. Love that you are putting out the information that will make sure that you are the best products on the market.
This reminds me of the false assertion that "Reducing engine rotating mass creates MORE Horsepower".
It does NOT.
The many examples where they try to "Prove" this using inertia Dynos are perfect examples of cheating.
They do a dyno run with the stock engine rotating mass on an inertia Dyno, then they reduce the rotating mass and do the dyno run again showing an increase in HP.
The part they do NOT tell you is that the software in the Dyno NEEDS TO KNOW the engine rotating mass.
If you DONT update the rotating mass in the software for the second run, then OF COURSE you will see an "increase in HP".
This is CHEATING. IF you update the correct engine rotating mass in the software you will see NO CHANGE in HP.
I had an STi that I had built (over 10 years ago now) at a shop that had a Mustang dyno. It was a Stock Turbo E85 car with bolt-ons. Put down 335whp and 375wtq on their Mustang dyno which is actually pretty decent. I went to the track thinking it was going to run at least mid 12's. I barely squeaked out a 13.2 @ 103, flat foot shifting it and with a 1.6 60 foot, so it wasn't a driving issue. DA was in the 1800's too so that wasn't an issue. I posted the dyno graph on an STi forum and someone pointed out that they were using a 1.23 correction factor! So pretty much they were showing crank numbers, lol. Ever since that experience, I take dyno sheets with a grain of salt.
note for european guys expressing power in kW and torque in Nm: the correcting factor is 2*pi/60000, so power in kW = torque in Nm * rpm /9549.3, so if you use the same scale on the y axys the torque curve and power curve meet at 9549.3 rpm, which is unrealistic on the vast majority of engines because they meet the redline way below (my car engine for example redlines around 6000rpm), so in a european dyno sheet the power curve is completely below the torque curve.
Excellent presentation.
I've seen engine builders, even on TH-cam, putting engines on their dyno' and running them barely warm, even cold, with electric water pump drives when it'll be installed with an engine driven pump, no fan or other parasitic accessories, open exhausts, no air filters, etc, and saying that's what the power of the engine is. IMO, means SFA - what matters is what the engine produces IN THE CAR, with everything in place!
Even worse, they'll 'tune" the engine under those SPECIFIC dyno' conditions and then send the engine to their customers - I've a better chance of winning the LOTTO ten times in a row than they have of getting the " tune" correct for the vehicle.
Other tricks are using different tyre pressures and/or running them cold vs hot, using different tyres and/or wheels, etc.
Excellent explanation for the 5252 correction factor - so many people parrot it without understanding a thing about it or how it was derived (it's 5252.113112 ... - but it's close enough).
The crossover only works when the same scale is used for both torque and power, so if a graph looks funny, first check that.
Hmmm, bit of an earth tremor there - some part of the country's been woken up this morning, and after a couple of minutes still some light movement... [edit] No hassles, it was just a 5.something.
Alternate video title: How to test engineer; engine testing PoV.
Much of the stuff you bring up, like the basic idea of bringing the 'test item' to a stable state prior to doing any actual measurements is test engineering 101 and can be applied to any testing. Great video.
this video is phenomenal. lots of backyard tuners and builders seem to forget that tons of mechanical engineering knowledge goes into properly measuring torque and power correctly and the differences people see from dyno to dyno are likely the result of a lack of knowledge with no intended malice.
the point about observed horsepower is a very good one to make though. I live somewhere that does have a substantial altitude compared to what one would expect an SAE spec dyno test to run and ill likely never see the numbers shown in said SAE test on the road.
I don't know why this was on my YT feed, but I watched it all & it was interesting. It becomes another piece of trivia that I'll probably never use. That 52 52 calculation is easy to remember, as long as I remember how many weeks in a year.
That was very usefull thanks.
Recently had my car tuned at a good friends shop. Made around 195HP and good power to 9500.
Back home i did some fine tuning and corrections and it made 120hp (exactly stock lol) on my dyno. Reverted all changes back to the 195hp tune and still got 120hp.
Wouldnt even want to rev past 8000.
Tought my dyno broke and was loading the engine down, but other cars measure correct on mine.
Tought he did some tricks but he dyno sheet is legit. IDK anymore
You guys are great at sharing knowledge. I had a foggy idea and could catch a really bad cheater, but now I have a good grasp of all the major deals and math. Keep up the good work.
Hats off to you Erik, and the Banks Team. Great video and I learned a few more things, such as how some skew their numbers. A lot of this is common sense such as repeatability and keeping the inputs as close as possible to get those outputs. Never thought someone would use different atmospheric conditions to show any kind of a difference. I have a Data Logger that I installed with a Pedal Monster, collecting lots of data on my 2021 Ram 6.7 HO, and have a Monster Ram sitting in a box ready to install. You can bet tubes and air box will be next on my list. It will be fun comparing all the data. And yes, I have the rear Dif cover.
What a great video. Dude your presentation skills are awesome. I don’t watch many Banks videos (though I respect the heck out of Mr. banks) but I’m glad I took the time to watch this one.
Large corrections can be useful(IF applied properly. It is done every day in aviation.), but I wouldn't put too much faith in them for comparing the tune of individual vehicle mods from two very different locations. A correction for changes in weather between two runs at the same location and vehicle is very appropriate. A large correction would also acceptable if the two stations have their correction formula cross checked with a reference engine, but this would mostly apply to a manufacturer's quality control of a specific engine design, rather than being suitable for a wide range of vehicles.
Great stuff guys!! You just packed the last 3 years of my learning into a 20 minute video!! 😂😂
Good job on calling them out! I see lots of bogus dyno numbers on TH-cam.
I'm glad when I was tuning my big block Mopar on my friends Dyno we found the best tune but most importantly the Dyno gave me the numbers I need for proper gearing and converter stall. That's all a Dyno is, a tool for tuning and stuff like I mentioned.
This was awesome. Thank you to everyone at Banks for being real. It's so rare.
Heaps of knowledge and truth; everything people having been coming to Banks for decades, and yet we can still learn something!
I had to pause the video when you said gotta dyno cars for hours to say you're right.
I had a 1986 Ford Festiva and loved it! I could fit a tile saw in it, or a paint pump. I got nine gallons of gas a week and could park on a sidewalk (don't do that) but it was awesome.
Anyway, when you have 90 squirrels turning the wheel in on Portland freeways, you're floored at all times that you're not going five miles an hour in traffic. Sometimes coming back into Portland heading down hill I coulda had 95 squirrels.
Bought it for $100, drove it for 20k miles and sold it for $400. $250 in maintenance, made thousands working with it, saved at least a few thousand in fuel and maintenance...best car I've ever had.
Really good video. Another point to consider is that sometimes correction factors should not be applied because the calibration has a torque based model - that is some calibration strategies predict torque and hold it constant for some range of ambient changes, specifically turbo charged engines. It then gets really messy at high altitude as the performance will drop off as turbo speed limits, surge limits compressor out temperature limits are hit and this can not be estimated purely based on the performance seen at one condition.
I always look at 5252 rpm to see that the numbers are the same but I
also look at 2626 rpm on Diesels where the hp is 1/2 the torque and on high
rpm engines I look at 7878 rpm where hp is 1 .5 times torque. I would like to
see the printout on the exotic Aston
Martin Valkyrie engine that reportedly
puts out about 1000hp at about 10500 rpm which would be 500 ft lbs of torque.
Also have noticed the some dyno operators pay some attention to water
temp but don't even mention oil temp.
I work around high performance boats
and have installed oil temp gauges so
I can size oil coolers. Started doing
this in the early 1970's. A lot of speedboats have oversized oil coolers
without oil thermostats and run low oil
temperature and some also run low water temperature.
Some Car dealerships will give you an estimate on your trade in value from a poor area where cars aren't selling for much, and then they show the value of thiers from somewhere in California, or maybe New York City
I supercharged my mustang. I had it on the dyno when it was 98% stock (it had a catback) and on the dyno after the lth, supercharger and water meth kit. I don't focus too much on the numbers. I just know the car is way more fun on the street now.
Thanks for the data. Trust you guys to call out the the cheaters, OOPS, ill informed," we didn't know better" crowd.
Awesome video.
I am amazed at how much information was packed into this video and how well the dinonomiter was explained.
Thanks!
Thank you for watching! More on the way.
Dang, Eric nailed this one!
This is an excellent video explaining how horse power can be different if not using correction factors and elements when using a dyno to calculate real horse power. As a heavy-duty mechanic it kills me to see car and motorcycle dyno's just consist of a quick rev up and giving inflated numbers. I worked for Caterpillar for ten years in their engine division. I was par dyno certified. I chassey dyno trucks and engine dyno engines every day. Even though the electronically controlled dyno would calculate the correction factors you had to know how to calculate the correction factors by hand. Knowing all this I could manipulate the horse power readings and fuel rates per hour and Caterpillar generate new "new fuel numbers" for the engines computer. It was a way to secretly get more horse power out of a stock engine especially if it was still under warranty. you could increase the horse power by 25% just with fuel numbers. Using the Wong software could get another 10% of horse power. Using wrong cams, injectors and turbos could add up to 30%
The fun ones are when they don't show the weather readings, and they stick the weather sensor somewhere hot and damp when it isn't, thus artificially inflating the true numbers. I agree the best method is observed power vs corrected when tuning your own car. I'd even say its best when doing a direct comparison of x part vs y part, provided the conditions are similar enough. Also goes to show you that when companies advertise gains over stock, its best to see who else has run the stock one to see if the numbers are skewed.
I destroyed AFE employees online back 8 years ago when they were posting dyno sheets that tq and hp crossed at 4000 rpm. They ended up removing all their dyno sheets online and starting over. Never buy their products
Finally a car video that makes sense from an engineering standpoint.
And, this is why Banks is the leader in performance gains!
It would be cool to see a “report card” on different auto manufacturers’ honesty about the power their cars make. I’ve heard (but can’t confirm) that Ford tends to “undersell” - dyno testing with regular pump gas and giving real-world numbers, whereas others tend to test in optimal conditions.
Chevy is great about this the LM7 is advertised at 270 to 295 flywheel hp but it actually usually puts that to the rearwheels, so they dont overinflate numbers.
And now we know, thanks for the schooling folks.
As always, excellent educational information!
Glad you enjoyed it! Thanks for watching.
Great video! Makes the whole "dyno mess" a lot easier to understand, and also, why you shouldn't use the "special price for you my friend" type of dyno shops.
Last time when Gale talked about your dyno setup, I had a run on the dynos in somewhat close range (within 4 hours drive). Non of them could boost a similar setup.
I live in Norway, and temperature/humidity is way off and CF is needed. Most companies I talked to, claimed that was the reason for them to run the dyno indoors and why they needed hood open and basically checked all boxes on "how to catch a cheater" :D
Well even if you have a 100% legit dyno. A other dyno can give you a bit of a fake number. But if it is just your car that you dyno before a modification and later just fine tune it. If the numbers go up and all value is good i think that what the number of the output on the paper is not the big deal. Many people overestimate the numbers what an engine or parts is given. Also even if it can boost the HK/Nm up. In the long run the HK/Nm will drop. this is for temp is rising and the turbo is just pumping hot air.
Here in the north. many shops have the dynos inside just for the use of all day. It is easy to have a controlled temp of like 20C. But the temp can be like -20 and + 30. that is a bit to much to just CF of. The next parts is that it is expensive stuff and noise regulations. Or you can have a dyno test without the rear wheels or on the open road. HK/Nm is just a number. Some one is always going to fly away from you on a car that have a different gearbox. not so heavy car. single driver without passenger and so on. Change the wheels and you need to re dyno if you like the number on the paper.
I have a B5234T5 that i am going to see what the numbers can be. The shop have dyno quite a lot of that engine or family so even if i can say that my numbers would be around 550-600hk, i think that a 450-500hk is more fare. and even if you have a big number on the end. The car / engine can be very boring to drive on what you are using it fore. I would rather have a ECU map that have power in the "fun part" of the register and not just in the 6000-8000 rpm range. A very fast car can be dead slow on a track where there is no long parts for the engine to use the higher rpm.
That was so much better than I thought it would be. I expected a lame rant about everything always crossing at 5252 RPM. Since you can scale HP and Torque separately on the screen, they can, visually, on a chart, cross at any RPM that you have torque data for. Using real math to check the results, perfect. On a side note, I'm always a little amused then the air filter tests on Dynojet dynos show the run numbers in the screen shot. Something like Run.003 366HP, Run.023 399HP. It took 20 runs to test an air filter? Or was it 20 runs to get the day's max run?
I believe the actual setup of the DYNO can make the numbers higher as well. For instances altertering the weight of the roller will effect the numbers.
well even the expansion of the rubber on the wheel gets a little bigger when hot or in higher rpm s. So the number youget from a dyno is more the number for you self and if you go back when you have upgraded or changed something then you can see if the numbers or curve have changed. the digits on the bottom on the page is more a " fun part".
Finally someone calling BS on all these dyno scammers
Informative video. I hate it when dyno ops engine start wait 5sec then go full WOT without considering ECUs have startup strategies aside from the fan/cooling strategy. Tricks at why you can get a dyno tune and still blow the engine cause the AFR wasn't dialed in steady state.
Also wonder why you see all these 700+rwhp vids, but then show hwy runs that lose ZERO traction or trap >10.5©135...well that's dyno magic...
Bank's Power is a University... AWESOME!
I send to all Motorsports contacts here in Brazil.
REGARDS!
Onje thing I do like about thw Ford is that in manual mode it will hold whatever gear you are in regardless of rpm or throttle position. You can lug it full throttle in 6th gear at 30mph at 1100rpm and it will not downshift. So if you really want to use thw available torque down low you can.
i learnt all my stuff from steam, so there was another one, indicated horsepower... the pressure in the cylinder over time. shows efficiency of the engine itself. the crank, the eccentrics... so much potential in the pressure, but only so much makes it out as actual brake horsepower, flywheel power... (not going to make this long, but imho, if the ICE is to progress, we have to overcome the inherent mechanical disadvantage of the crankshaft being at TDC when the maximum pressure is being applied to the piston... it has to act tangentially at TDC, not radially. ideally tangential for the full duration of expansion. figure THAT one out, and the entire nature of the ICE as we know it will change... as it is, the ICE is a glorified steam engine with spark plugs, an air compressor that drives itself with a little bit of output on the side. petrolhead my whole life and i HATE THE DAMN THINGS! anyway... end digression.)
sweep time is highly under-rated... and its critical for carbs. it gets into the emulsion tube side of things... EFI just masks all the issues out as its main intention is deliver optimum fuel for any condition...
at a fixed throttle setting, air speed through the venturi is based on RPM alone. the suction on the jet is determined by the air speed.
as RPM increases, air speed increases, jet suction increases, and the mixture gets richer and richer.
the suction on the jet rises at a square? cube? its a non-linear curve, air speed to suction. vacuum. pressure differential. sigh... terminology matters!
emulsion tubes allow progressively more and more air leak into the main jet and lean the mixture out, make it ideally linear with air speed and RPM. or closer to what the engine demands, anyway.
as you get higher and higher power levels it gets harder and harder to try and tune this... on a cruddy little 5hp engine gokart, barely accelerating... you can FEEL the emulsion tube as you accelerate... start playing around with the holes and you really start to notice! flat spots and bog through the RPM range on one throttle setting.
and as no-one really understands emulsion tubes at all, they start changing jets and needles and clips (im a motorbike guy...) instead and forever chase their tails...
bikes are particularly fun as they have such a wide RPM range, and CV carbs are just another level of mindfukkery... youre trying to isolate several overlapping and interacting circuits but arent even made aware of one of the fundamental ones, how emulsion tubes work.
yeah, i made a dyno. eddy currents rule. conductor (6mm copper plate) magnetic field. easy.
you didnt mention how fast they heat up! im limited to about 100kw simply due to heat... that is a LOT to get rid of.
and to think, the engine is actually throwing away another 300KW or so... like, a standard heater is only 2.4KW!
I Can't believe how much I just Learnt in 20 Min's!! Thanks very much, very interesting Indeed!
That simple relationship doesn't apply to combustion engines, or more specifically it does but not the way it might seem - it's the downward torque on the piston. The power is directly related to the conversion of chemical energy, which determines the downward force on the piston. But the torque determines on the leverage the piston has on the crankshaft, which is by definition half the stroke length at its peak (at 90˚). The stroke length creates a relationship between rpm, torque, and power (or force). The simple relationship is the torque of the _piston_ , but this is then geared through the piston shaft onto the crankshaft. It DOES apply to electrical engines, where it is the relationship between electrical power (minus losses) and torque. In addition, engine timing optimized for power is optimized for _airflow_ , and hence maximizes intake and exhaust valves open times, power is then created by running higher rpms (more combustion cycles = more fuel chemical energy released per second = more power), whole torque is optimized by keeping valves _closed_ to maximize the time the downward force can act on the piston. This leaves less open time, and as rpms go up the mechanical tolerances makes it impossible to maintain the short open angles, and so puts a limit on the rpm sustainable and hence peak power. A longer stroke also means the piston has to travel faster at the same rpm, due to the implicit gearing.
Do note that in different units, the crossover is at different RPMs, in metric for instance it happens at 9550rpm (kW and Nm)
I have run and tuned bikes on five different DJ chassis dynos (over *17,000 dyno runs* logged) so I can confirm what's been said here.
1: making pulls before completely warming EVERYTHING up does make a difference. 2: doing pulls in different gears makes a difference and 3: using load control during pulls (longer sweep, slower roll-on rate) for sure makes a difference with both "proper tuning" and HP numbers.
But I'm also adding that the *TIRES* used can/do make a difference as well. I've done back to back testing several times over the years (swapping identical wheels with different tires mounted on them = less than 10 minutes between test pulls). The OEM tires always show the highest numbers while most Drag Radials on bikes "rob" somewhere between 9-12Hp and (not kidding) Drag Slicks rob 15-20+Hp (with data confirming there was no tire spin/slippage on any of the tires tested).
But since everything about racing is give and take, the added traction (when needed) far out weighs the loss of power...
And lastly (my experience with slower roll-on rates).
What surprised me the most is, simply adding a few % of duty cycle to the Eddy Brake (longer sweep time) makes a 20Hp difference =10% on 200 RWHP bikes...
Great info, I still have a question. Chassis dyno measures the torque at the wheel, we know the resistance of the dyno roller and hence the torque at the wheel. Torque at the engine flywheel (all dyno charts are made to look like they come from engine RPM) would still need to be calculated using current gear ratio, differential ratio and the ratio of dyno rolller diameter to wheel diameter, correct?
We have ONE shop in my area this thorough and I appreciate them. They just moved into a facility twice the size of their old one so I'm sure everyone else does too.
Excellent video tutorial - very well presented. You can be sure that I'll be back for more. Thanks.
The work on the JLTV is why I want Banks in my truck
Excellent video. Thanks for all the information!
I caught a local performance tuner fudging the numbers on my built 2012 EVO MR. I used their service since my friend's shop was booked out 4 months. I bribed my friend with beer and we dyno'd my car after hours...there was a 20% difference. Same model and type of dyno. Same type of runs. Same tank of gas. etc.
Eric you certainly have been listening to you grandfather. Great explanation.🇦🇺🍺
i dont care who these guys are.. i just hit subscribe for the content they does
19:23 your dotted line power curve doesn't cross the torque curve at the same place.
I'm wondering how you can get the standard atmosphere humidity at zero percent. It gets into the single digits around here sometimes but zero seems impossible.
Also, when you "photoshop" the graph the crossover does not happen at 5252 rpm. Just one quick way to disqualify a fake. 😉
So does the vehicle weight that's input into a Mustang dyno skew results? My original tuner had my car in at 3800lbs when I'm actually 4200lbs. What about all the other factors like friction coefficients, drag, frontal area, etc? Great video.
Were they calculating theoretical acceleration times? If not, vehicle weight / frontal area and so on will have zero effect on dyno testing.
There is some good information here, but most chassis dynos don't measure torque. They measure hp and then calculate the torque based on what rpm the hp was achieved.
I tested my 03 Cobra on two types of dynos when 100% stock. An eddy current Mustang dyno and a Dynojet. Both were at sea level, but temps were about 20 degrees colder when on the Mustang. On it, the Mustang I made 355 hp on the Dynojet it made 372 hp which I thought was interesting.
Dynojets are generally acceleration dynos that measure horse power and back calculate torque where as Mustang is a loading dyno that measures torque and calculates HP. Say you put heavy wheels on the car, this will slow 1/4 mile times due to the added inertia and will lower acceleration dyno results but will have minimal to no effect on a loading dynos results.
Great stuff, that's why Banks is the leader it doing things right!!!
Aaaah. Finally some content with content. 😂 Where’s that subscribe button…
I caught this with Cleetus McFarland recently. I think it was done out of ignorance rather than purposefully, but they dyno’d they’re giveaway 10 speed F-150 in 4th gear instead of 7th. Seemed wrong to me at the time to still be in 4th, now I know I was correct. Although there were more losses in the run, I think it showed more horsepower due to the uneven ratio
I believe they did that due to wheel speed, but I don't remember.
Why it should have showed more power on 4th?
Nice presentation. Good job Erik.
4:25 I thought multigrade engine oil gets *thicker* with higher temperatures?
Yes and no. It gets to a higher viscosity rating, but that rating is based on a test performed at a set temperature. So a 5w-30 oil acts like a 5 when cold and a 30 when hot**, but a hot 30 is still thinner than a cold 5. Try heating up some 20w-50 on the stove to 200 degrees and see how it pors compared to 0w-20 out of the bottle. The multi-weight is there to reduce the thinning effect of heat, but they can't reverse it.
** The description above will get you the understanding, but I did lie slightly. When I compared a cold 5 to a hot 30, those numbers are not exactly equivalent. So like on a 5w-30, that 5 is based on one test and the 30 is based on a totally different test. Gear lubes and other oils all have their own different tests, too. So you know that 5w-XX motor oil is thinner from cold than a 20w-XX, but that 20w is not actually equivalent to the hot rating of an XX-20 oil. It IS still true that a hot 30 is thinner than a cold 5w, which you can verify with 5w-30 on the stove, but just know that those numbers aren't directly comparable to each other.
@@JETZcorpthanks for the explanation, I'm surprised that cold and hot ratings are not comparable.
@@NumbByDawn The different tests definitely make things confusing, but there's a reason they do it that way. Each test is optimized to score the performance of the oil in the environment that the number is trying to tell us about. So the 5w number in 5w-30 is tested cold and the 30 is tested hot, and those numbers are based on some imaginary fluid devised for the testing standard. If you took a straight 40wt oil (which means it scores a 40 in the hot test), and ran that through the cold test, it probably wouldn't score a 40w. If you took 5 different straight 40 oils, they'd probably all get different cold test numbers, because lots of things affect how these oils change with temperature, and motor oil has a lot of stuff in it. If the numbers represented the same thing, it HAS to mean that either the test or the oil is the same. Having different tests gives more relevant information, but it's just not as clear. The difference between the w and second number is not THAT big, though. It's just the correction factor.
Now, where things really get funny is when you compare different kinds of fluids. Those tests are TOTALLY different, and the numbers mean nothing relative to each other. For example, 20w-50 motor oil is slightly thicker than 75w-90 gear lube.
Just like testing a cold air intake with the hood up there are a lot of companies that do that but they think most people don't know exactly what they are looking at. GREAT VIDEO and Banks is one of the best companies not only for their parts they call out other companies 💩
Okay, I've aways wondered where the 5252 constant came from. This got me mostly there.
I am curious how the chassis dyno compensates for the diff gear ratio and the tire size. Are those variables the operator has to input? Because it seems like the diff gears would be a torque multiplier while a bigger tire takes more torque to turn.
What transmission was illustrated at 6:56? The only five-speed that I know intimately is the nv4500, and this is not a nv4500.
Your videos are always top-notch.
Thanks for taking time to explain it!
Last time I read a dyno spec I'm sure it said any correction factor not to exceed 5% in total and not to be applied to anything that uses forced induction.
My MR2 has a side mounted intercooler and intake. Do dyno shops properly put fans at all important areas? Also...if a fan is mounted by the intercooler, is it blowing from the side or like a real world condition as lateral air flow? Good info on the rest of the video.
Hopefully this vid gets more hits as Banks has always been a no fluff straight shooter just the facts kind've guy: cudo's to him and his employees. Thanks for saying your dyno only reads "Torque". Most ppl dont understand what the Horsepower phenomenon actually represents and will say grossly misunderstood things like, "Its HP that wins races"! HP is a dimensionless unit and cant exist without Displacement, RPM, and being tied in to the TQ/HP equation. HP is a qualifier of how effectively, (efficiently),TQ is being applied at a per minute per second time frequency. Not only is it a measurement within a time frequency but also a qualification of the 4 Cycle Engine; as in 4 Strokes, specifically the Combustion Cycle. HP is metaphorically qualifying how many times a hammer (Combustion Cycle) hits the anvil (Moment of Force) per minute. Technically ppl should say, "Its the Increase of the application of Torque at a specific RPM that wins races"; but thats too complicated for most, and bragging about HP is more fun. Because the Crank turns twice per one revolution of the Cam, we are dealing with 720° of crank rotation: all these #'s are inter'related. James Watt gave us the standardization of 1 HP per minute of 33,000 and 550 HP per second but never qualified the Power, at least not publically. Funny enough, because the brewary's draft horses turned a grinding stone in a 12 foot circle, RPM was actually qualified at 2.4 rotations per minute; however that was never pursued. James Watt did however utilize a Pressure Wave graph on his steam engines privately in the late 1600's but never applied for Royalties from the King or Engineering Guilds of the day; he kept his Pressure Wave graph tech secret. It took another 60 to 100 years before Pressure Wave tech was being taught by the Engineering Guilds. Until a person understands Radians they will never understand why the use of Pi, RPM's or why the 33,000 variable magically changes to 5252 in the TQ/HP equation. You touched on it when addressing Circular Functions of Rotational Velocity but didnt go too deep in explaining; this is already a 20 minute vid so theres only so far you can go. Afterall, its the individuals responsibility to educate themselves. Very quickly, a circle, (the flywheel), is 360° per 1 rotation. Take any size circle and half of that circle's circumpherance is 180° angle travel, or half a circle. 1/2 a circle is 1 Pi as in 3.14159in Radians. A whole circle is 360° or 2 Pi, as in 2 x Pi, as in 6.283 as in 1 Radian. Take RPM which is Revolutions Per Minute and apply that to James Watts 33,000 ft/lbs per minute and you get,
33,000 ÷ (2xPi)
33,000 ÷ (2 x 3.14159)
= 5252.11
There's your 5252 variable
You could use James Watt's 550 HP per second but then you would have to divide 60 into 2Pi. The 60 represents 60 seconds per minute while 2Pi represents Radian Velocity of one Revolution.
2Pi ÷ 60 = .104716 (Radians Per Second)
Now divide that number into James Watt's 550 HP per second and,
550 ÷ .104716 = 5252.30
Now to get from the Imperial Tq/Hp numbers to the UK's NM power dyno graph simply multiply conversion factor 1.8181 by the 5252 variable
5252 × 1.8181 = 9548.66
Why does this 5252 variable work. Break down the math and you get 2Pi (Radians) per 1 Revolution, Rev's per minute, and 60 seconds per 1 minute. Simply put, Rev's ÷ Seconds ÷ Radians, written as,
(38 ÷ 1) × (1 ÷ 60) x (2Pi ÷ 1), the 1's will cancel out, the 2 and 60 are minimized cleaning up the equation as
(38 ÷ 30) x 3.14159 = 3.979 Radians per second. Now there's a little history behind the TQ/HP equation. I could go on but this is long enough already. Thx for making your vid
PS: I've been watching Banks stuff since the late 80's, always good stuff
Very interesting. From a tuning perspective, could you give a run down on how changes to those things might effect different parameters that are being measured? Say we are trying to do an IM240 or an RG240 test (Repair grade? I think it’s called) to confirm emissions compliance. Are we likely to get different results or would it be possible for someone to cook the results, leading to either a pass or a fail?
I used to work at a shop with a dynojet Dyno.Horspower numbers can be easily manipulated.
5:40 if sweep time is short and engine rapidly accelerates, there are loss of acceleration of intaked air,( and all mass )-for ex when i accelerate in 2. gear usually happens lean mixture, because my lpg system is not dimensioned for that flow rate but when accelerate in 3. or 4. gear at same rpm , no problem, so at rapid acceleration, must accelerate at high rate so in intake is more resistance than if it accelerates slowly
Can you guys do a video explaining how pulling force works? Im an engineer and when i see peoples comments on a video of an f150 lightning pulling a one million pound train then asking how they found a rope that can hold a million pounds it just boggles my mind. Most people don't realize that the straight line pull force from their truck is less than what their truck weighs. Along with that, it'd be great to show how much the coefficient of friction changes when you start spinning your tires. You guys seem like the only ones who could explain this well enough to make everyone understand.
A Toyota pickup pulled the space shuttle over a bridge while the SS was being moved to a museum. Be sure to note that a 1 M LB rope was not needed as rolling force for a wheeled vehicle in good condition is going to be less than it's weight / mass. The key to moving a very heavy object is a slow change in velocity so as not to exceed available friction.
You could probably find discussions on that in tow truck related channels.
Also take a look at climbing gear. It gets rated by force, not weight.
It ends up being kind of the HP vs torque discussion. You can move something on wheels that weighs a million pounds if you keep the acceleration low. A few hundred pounds of force should move that train. Steel wheels on steel rails keep rolling resistance down vs pneumatic tires.
@@immikeurnot I'm well aware of the physics behind it and can show the math to support it but unfortunately a comment isn't quite as impactful as a well done video by a respected company.
Aye I think old man Banks is my long lost grandfather I never knew 😂