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oldcorollas Forums Junkie Location: Kita-Ku, Sapporo, Japan Registered: January 2003	Re: TORQUE Tue, 24 June 2003 09:32 rusty wrote on Tue, 24 June 2003 18:33 oldcorollas wrote on Tue, 24 June 2003 17:17 what you forget to mention is gearing. your electric motor idea. one motor, 1Nm@1000rpm, second = 1Nm@20000rpm. the second motor does indeed have more power, but if connected thru the same gearing, will have the same accelerative force at the wheels as the first motor. to use power effectively, you have to take advantage of GEARING. very true, so far. but you shot yourself in the foot there, as you seem to have forgotten to examine what happens when you gear the car so both those cars with their respective rpm are at the same "road speed"? when you drop the flag the car with the gearing set for the motor to turn 20,000rpm will leave the other car for dead. but the engines of both are still making only 1Nm. and again i quote myself as you didn't read the last sentence "to use power effectively, you have to take advantage of GEARING"you also didn't read further into the message where i talk about gearing of the F1 car? rusty wrote on Tue, 24 June 2003 18:33 remember, torque has no motion. torque is simply twisting force. with motion comes power. if torque was all important, the f1 boys wouldnt bother with the huge hassle of engineering a motor to turn over 18,000rpm (theyre close to 19,000rpm this year). but they have a gearbox with more than 1 gear plus they know that power is what moves the car. LOL, you have nfi. they build motors to turn at high revs so they can gear down and muliply the torque at the axles, and so FORCE that the wheels apply to the track. they do this because for any given capacity there is a THEORETICAL MAXIMUM amount of torque that it can produce and so to take most advantage of a restricted capacity size they have high revs and gear down... READ THIS PARAGRAPH TWICE BEFORE GOING ON!! rusty wrote on Tue, 24 June 2003 18:33 actually its not there are many sayings in the automotive world. another is that "there is no replacement for displacement". i wonder if you ascribe to that one also? yes there are many sayings. there is no replacement for displacement IF BOTH MOTORS HAVE THE SAME EFFICIENCY AT THE SAME RPM. find me a V8 that revs to 9000rpm with volumetric efficiency above 85% of ideal and i'll trade in my 1.3L 4K. find me a stock 4K and i'll laugh at you as i fly past. my motor made 47.2kw at the rear wheels at 8000rpm on dyno day 5. if you get a 5L motor that makes 181rwtmddkw (rear wheel toymods dyno day kw) at 8000rpm, then why not use it? it's all about efficiency and gearing dude. increase both for more acceleration. rusty wrote on Tue, 24 June 2003 18:33 oldcorollas wrote on Tue, 24 June 2003 17:17 BUT, for the same car speed, the F1 motor will have a GEARING advantage of 3:1 over the normal car engine, and so the TORQUE AT THE WHEELS will be 3 times higher, so for a given car mass, will accellerate 3 times faster. it perplexes me that you mistake power for torque above, yet go on to state the following .... oldcorollas wrote on Tue, 24 June 2003 17:17 two cars with identical POWER at different rpm, at the same road speed, will accelerate at the same rate, since GEARING multiplies the torque of the motor with higher rpm at same power. clearly power is accelleration, not torque. you even said it yourself. you obviously did not not read either of these paragraphs. i think you shoudl re-read them. hell, i'll even spell it out for you. F1 vs normal car engine as stated in previous message. F1 has 3 times power because of higher rpm. F1 car has 3:1 gearing to be at same road speed as normal motor. F1 car has TORQUE multiplied by 3 because of gearing. F1 car has 3 times the torque on rear axle. f1 car has 3 times the force at tyre contact patch. F1 car acclerates 3 times faster. conclusion? the F1 car acclereates faster because the gearing gives it more force at the wheels. the gearing is allowed because of higher engine rpm. power is a convenient way to compare cars ASSUMING they have the necessary gearing. if you can't follow this thread of maths, please don't respond. torque = force times by distance. increased torque AT THE AXLE = more force at the contact patch between tyre and road. are you seriously trying to say that if you have less force at the contact patch that you will accelerate faster? a cars acceleration is governed by the laws of physics, namely F=MA, where force is at the tyre contact patch, mass is the mass of the vehicle and acceleration is what you are trying to achieve. power is not acceleration.. how can you possibly say this? power = Nm/s, acceleration is m/s^2 do you have a year 9 physics text book? rusty wrote on Tue, 24 June 2003 18:33 ever wonder why engineers look at power to weight, to gauge performance, and car mags list power to weight among a cars spec? because acceleration is the result of power to weight. and because torque to weight is irrelevant i occasionally marvel that such a simple issue as this is so commonly misunderstood. the reason is that a lot of people with only a loose grasp of the concepts try to explain on forums such as these, yet keep contracdicting themselves. its no wonder then that the novice becomes confused. dude that's just horseshite and heresay, and assume that the cars being compared have gearing for the same top speed (at engine redline perhaps?) another example for the more dim amongst us. rally cars, WRC to be specific. they are geared so that top speed is about maybe 180kph? if they were geared to match an F1 cars 300+, they would accelerate slower. and again with WRC cars. they are limited in POWER to 300ps/hp, but there is no limit on torque. so they make their torque (all 500Nm of it) at lower rpm to get around the power limit. tell ya what. lets get two cars, that have the same gearboxes and same final drive ratio. i'll take the car with 500hp at 5000rpm, and you can take the car with 500hp at 10000rpm, and i'll whup your sorry ass . if you don't have the gearing you can't multiply your torque and you are slower cos you have less torque at the wheels... but you will have a higher top speed, since you will rev to higher rpm. engineers look at power vs weight because it is much more convenient than trying to calculate gear ratios and different redlines for motors and stuff like that... did you know that there are no actual requirements to become a certifying engineer in NSW? i actually checked when i finished uni to see what would be needed, so i could be one. i was told that there is a guy that decides, and his criteria are about 15-20 years experience in the motor industry and a general knowledge of cars. no tafe tickets, no degrees, no certified knowledge required the only loose grasp here is the relationship betwen torque and power that you have. (did you read the equations thread for calculating theoretical power and torque?) what it comes down to is that: a mass is accelerated by a force (F=MA) the force at the tyre contact patch = torque/wheel radius or (FTCP = TQ/WR) so FCTP =MA and TQ/WR = MA so A = TQ/MxWR to increase accleration, you either increase torque (by gearing multiplication), decrease your mass, or decrease you wheel radius. sure power is a convenient way to measure motors, but it really doesn't mean that much. WHAT IS IMPORTANT is the TORQUE an engine makes and the ENGINE SPEED (rpm) that it makes it at. as i have said from the start, if you make the same torque at higher rpm, AND gear down to increase the torque multiplication, you will have more torque at the rear wheels, adn you will accelerate faster. these are the simple physical facts that govern our everyday life. please bring your reference notes (where you are getting this info from) to the dyno day and i will show you why you are wrong. or even better, how about someone pushes you and you fall over, then get two ppl to push you over, you will accelerate twice as fast with two ppl pushing you seriously tho, you ned someone to guide you through the equations that govern how a car accelerates, otherwise you will be stuck in this idea that power matters and torque doesn't. i apologise to the people who did not turn off the 'email notification' of this thread, but i hate when ppl propogate half truths. Cya, Stewart [Report message to a moderator]

	Subject	Poster	Date
	TORQUE	BAD22	Sat, 21 June 2003 04:43
	Re: TORQUE	oldcorollas	Sat, 21 June 2003 07:20
	Re: TORQUE	trent_kershaw	Sat, 21 June 2003 09:52
	Re: TORQUE	wilbo666	Sat, 21 June 2003 12:29
	Re: TORQUE	BAD22	Sat, 21 June 2003 13:06
	Re: TORQUE	TA22-3SGTE	Sat, 21 June 2003 13:20
	Re: TORQUE	gianttomato	Sun, 22 June 2003 02:18
	Re: TORQUE	rusty	Mon, 23 June 2003 19:37
	Re: TORQUE	BAD22	Tue, 24 June 2003 01:57
	Re: TORQUE	oldcorollas	Tue, 24 June 2003 07:17
	Re: TORQUE	rusty	Tue, 24 June 2003 08:33
	Re: TORQUE	oldcorollas	Tue, 24 June 2003 09:32
	Re: TORQUE	gianttomato	Tue, 24 June 2003 09:42
	Re: TORQUE	Gremlin	Thu, 26 June 2003 02:16
	Re: TORQUE	rusty	Tue, 24 June 2003 10:29
	Re: TORQUE	oldcorollas	Tue, 24 June 2003 11:12
	Re: TORQUE	gianttomato	Tue, 24 June 2003 11:46
	Re: TORQUE	oldcorollas	Tue, 24 June 2003 12:01
	Re: TORQUE	trent_kershaw	Tue, 24 June 2003 14:03
	Re: TORQUE	NO-18r	Sat, 21 June 2003 08:48
	Re: TORQUE	BAD22	Sat, 21 June 2003 08:49
	Re: TORQUE	manipulate	Sat, 21 June 2003 08:51
	Re: TORQUE	manipulate	Sat, 21 June 2003 13:10
	Re: TORQUE	BAD22	Sat, 21 June 2003 13:12
	Re: TORQUE	cam_RA40	Sat, 21 June 2003 23:17
	Re: TORQUE	JDM hachi	Sat, 21 June 2003 22:52
	Re: TORQUE	manipulate	Sun, 22 June 2003 01:55
	Re: TORQUE	charliechalk	Sun, 22 June 2003 11:26
	Re: TORQUE	BAD22	Sun, 22 June 2003 15:58
	Re: TORQUE	gianttomato	Mon, 23 June 2003 01:05
	Re: TORQUE	charliechalk	Mon, 23 June 2003 08:06
	Re: TORQUE	BAD22	Mon, 23 June 2003 10:00
	Re: TORQUE	Super Jamie	Tue, 24 June 2003 11:04
	Re: TORQUE	kingmick	Tue, 24 June 2003 12:18
	Re: TORQUE	THE WITZL	Tue, 24 June 2003 12:27
	Re: TORQUE	trent_kershaw	Tue, 24 June 2003 12:44
	Re: TORQUE	THE WITZL	Tue, 24 June 2003 13:06
	Re: TORQUE	rusty	Tue, 24 June 2003 16:35
	Re: TORQUE	juzzo84	Tue, 24 June 2003 21:08
	Re: TORQUE	boudan	Tue, 24 June 2003 22:49
	Re: TORQUE	Super Jamie	Wed, 25 June 2003 07:26
	Re: TORQUE and shite stirring	oldcorollas	Wed, 25 June 2003 12:27
	Re: TORQUE and shite stirring	oldcorollas	Wed, 25 June 2003 12:36
	Re: TORQUE	boudan	Thu, 26 June 2003 00:37
	Re: TORQUE	bayka	Wed, 25 June 2003 17:41
	Re: TORQUE	Norbie	Wed, 25 June 2003 22:37
	Re: TORQUE	dar_sbb	Thu, 26 June 2003 01:58
	Re: TORQUE	bayka	Thu, 26 June 2003 05:49
	Re: flat TORQUE curves	oldcorollas	Thu, 26 June 2003 06:23
	Re: flat TORQUE curves	Nark	Thu, 26 June 2003 06:45
	Re: flat TORQUE curves	oldcorollas	Thu, 26 June 2003 07:03

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