Motor Daddy Posted June 19, 2008 Share Posted June 19, 2008 (edited) RPM, Torque, and Horsepower Here is a prime example between two different engines with completely different torque curves. Engine A in second gear (1.98) with a 3.23 rear gear and 26.5" tire. 2000 464 lb-ft 176 hp 24 mph 2967 RWTQ 2500 482 lb-ft 229 hp 30 mph 3082 RWTQ 3000 496 lb-ft 283 hp 37 mph 3172 RWTQ 3500 511 lb-ft 340 hp 43 mph 3268 RWTQ 4000 506 lb-ft 385 hp 49 mph 3236 RWTQ 4500 481 lb-ft 412 hp 55 mph 3076 RWTQ 5000 427 lb-ft 406 hp 61 mph 2730 RWTQ 5500 363 lb-ft 380 hp 67 mph 2321 RWTQ Engine B in second gear (1.98) with a 3.73 rear gear and 26.5" tire. 2309 410 lb-ft 180 hp 24 mph 3028 RWTQ 2887 430 lb-ft 236 hp 30 mph 3175 RWTQ 3464 460 lb-ft 303 hp 37 mph 3397 RWTQ 4041 465 lb-ft 357 hp 43 mph 3434 RWTQ 4619 465 lb-ft 408 hp 49 mph 3434 RWTQ 5196 445 lb-ft 440 hp 55 mph 3286 RWTQ 5773 390 lb-ft 428 hp 61 mph 2880 RWTQ 6351 330 lb-ft 399 hp 67 mph 2437 RWTQ Two identical cars (except for engine and gears, same weight) are moving along at a steady 24 mph in second gear side by side. They both punch it at the same exact time. Which one will pull ahead immediately, and get to 67 mph the soonest, and cover the greatest distance in the same time period? The one with the greatest engine TORQUE, or the one with the greatest engine HP?? No takers on engine A?? Jeez, we debated torque and HP for 1,000's of posts in several threads on other sites. No car guys in the crowd? Edited June 19, 2008 by Motor Daddy multiple post merged Link to comment Share on other sites More sharing options...
nstansbury Posted June 19, 2008 Share Posted June 19, 2008 Not that I want to encourage feeding the Troll, but Motor Daddy - is this another "bait and switch" post? If it isn't, at least present your numbers in a way we can all understand, explain the point you are making, define your key issues, and show you understand any points made beforehand. Sorry to say this - but you have "previous". Link to comment Share on other sites More sharing options...
Motor Daddy Posted June 20, 2008 Author Share Posted June 20, 2008 (edited) Not that I want to encourage feeding the Troll, but Motor Daddy - is this another "bait and switch" post? If it isn't, at least present your numbers in a way we can all understand, explain the point you are making, define your key issues, and show you understand any points made beforehand. A bait and switch? What's that? I presented the numbers for each engine as follows: Engine RPM-torque at that RPM (as measured on a dyno)-HP at that RPM-vehicle MPH-rear wheel torque (axle torque) The point I make: Which car will get to 67 MPH the soonest and travel the greatest distance in the same time? The questions are clearly defined. Sorry to say this - but you have "previous". What?? A pic of the torque curves: Engine A is the 455 (blue diamonds.) They both use the same exact parts, except the 455 has a different bore and stroke. Surely you'll take the 455? Edited June 20, 2008 by Motor Daddy multiple post merged Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 Anyone care to take a stab at the problem? Link to comment Share on other sites More sharing options...
Klaynos Posted July 3, 2008 Share Posted July 3, 2008 Not something that interest me, sorry! Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 Not something that interest me, sorry! Mass, distance, and time doesn't interest you? Link to comment Share on other sites More sharing options...
Klaynos Posted July 3, 2008 Share Posted July 3, 2008 Fitting torque graphs and working from that doesn't, no. Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 Fitting torque graphs and working from that doesn't, no. So my math is incorrect? Link to comment Share on other sites More sharing options...
YT2095 Posted July 3, 2008 Share Posted July 3, 2008 Anyone care to take a stab at the problem? I`d dearly love to, but it`s illegal Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 I`d dearly love to, but it`s illegal Translated: The math is correct and I have no explanation for why the greatest torque engine loses the race? Link to comment Share on other sites More sharing options...
Klaynos Posted July 3, 2008 Share Posted July 3, 2008 So my math is incorrect? I dunno, your little computer program is a black box, I'd take the data points and fit a polynomial to them before doing any maths. Although it's nowhere near as trival as that as you've got different gear settups... So no this really doesn't interest me at all. Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 I dunno, your little computer program is a black box, I'd take the data points and fit a polynomial to them before doing any maths. Although it's nowhere near as trival as that as you've got different gear settups... So no this really doesn't interest me at all. Translated: I can't explain it. Link to comment Share on other sites More sharing options...
Sisyphus Posted July 3, 2008 Share Posted July 3, 2008 I don't know much about engines, but why wouldn't you expect the car with greater HP to win? That is, if the term "power" when talking about engines is the same as the conventional usage, meaning work per unit time. Isn't torque only important inasmuch as power is a product of torque and angular speed? EDIT: Also, chill out. Why on earth would this subject cause such hostility? Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 I don't know much about engines, but why wouldn't you expect the car with greater HP to win? That is, if the term "power" when talking about engines is the same as the conventional usage, meaning work per unit time. Isn't torque only important inasmuch as power is a product of torque and angular speed? EDIT: Also, chill out. Why on earth would this subject cause such hostility? I'm not being hostile. I always hear, "show us the math," so I did. Now, when the math is plain to see, it doesn't interest anyone? Link to comment Share on other sites More sharing options...
Phi for All Posted July 3, 2008 Share Posted July 3, 2008 Translated: I can't explain it.Don't do that anymore. It's rude to the people who take time out of their day to respond, it's bad logic and it's a very poor tactic that could come back to haunt you later. Link to comment Share on other sites More sharing options...
Mr Skeptic Posted July 3, 2008 Share Posted July 3, 2008 Motor Daddy, that is data, not maths. Which is still useful. Any maths included would be in the computer program. As to why no one is taking you up on your offer, it is because: 1) you have a reputation for being an asshole, 2) this type of problem is more annoying than interesting, 3) you probably already know the answer anyhow (see point #1) and will just mock someone who gets the wrong answer, or even insist that they are wrong if they got the right answer. Horsepower is the "wattage" of the car -- the more horses, the more power. You can change your actual torque on the wheels of the car (where it matters, as opposed to the engine), by changing gears. Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 Motor Daddy, that is data, not maths. Which is still useful. Any maths included would be in the computer program. As to why no one is taking you up on your offer, it is because: 1) you have a reputation for being an asshole, 2) this type of problem is more annoying than interesting, 3) you probably already know the answer anyhow (see point #1) and will just mock someone who gets the wrong answer, or even insist that they are wrong if they got the right answer. Horsepower is the "wattage" of the car -- the more horses, the more power. You can change your actual torque on the wheels of the car (where it matters, as opposed to the engine), by changing gears. You mean like the way some of the people on this board treat others ATM ideas? Should I post some quotes of people that get away with murder around here, and others that get banned for much less? Can you answer the question, with explanation? Link to comment Share on other sites More sharing options...
Mr Skeptic Posted July 3, 2008 Share Posted July 3, 2008 Can you answer the question, with explanation? I already did, in post #16. I also forgot to add that you are very hostile to people and that you are easily distracted from the topic, even in threads that you started. See post 17, for example. I'm not attacking you, btw, just telling you why people are wary of you. Feel free to go on a rampage, though, it will just prove my point. Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 3, 2008 Author Share Posted July 3, 2008 I already did, in post #16. I also forgot to add that you are very hostile to people and that you are easily distracted from the topic, even in threads that you started. See post 17, for example. I'm not attacking you, btw, just telling you why people are wary of you. Feel free to go on a rampage, though, it will just prove my point. Mr. Skeptic, Either answer my questions or stay off my thread, you are trolling. Link to comment Share on other sites More sharing options...
Mr Skeptic Posted July 3, 2008 Share Posted July 3, 2008 Well, you better stop answering my posts if you think I am trolling. That's called "feeding the troll" and only encourages them. Link to comment Share on other sites More sharing options...
Cap'n Refsmmat Posted July 3, 2008 Share Posted July 3, 2008 Let's try to stick to the topic of the original post, please. Link to comment Share on other sites More sharing options...
Motor Daddy Posted July 9, 2008 Author Share Posted July 9, 2008 Anybody have an answer yet? Link to comment Share on other sites More sharing options...
honestdude14 Posted July 10, 2008 Share Posted July 10, 2008 Sheesh, alot heat around here.. I'm gett'n outa here. Link to comment Share on other sites More sharing options...
Duration Posted March 25, 2009 Share Posted March 25, 2009 Anyone have an answer yet? Link to comment Share on other sites More sharing options...
Sayonara Posted March 25, 2009 Share Posted March 25, 2009 Necromancy, apparently. Link to comment Share on other sites More sharing options...
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