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Location:
Melbourne
Registered:
April 2003
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TORQUE
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Sat, 21 June 2003 04:43
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IS THERE ANYONE OUT THE THAT CAN EXPLAIN IN ENGLISH THE WHOLE Nm THING? WHAT IT MEANS AND HOW IT IS MEASURED? 
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE
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Sat, 21 June 2003 07:20
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easy as man,
1 newton metre (Nm) mean that you have a 1 metre stick with 1 newton of force at the end. a newton is the mass multiplied by gravity...
for example if you have 1 kilogram at the end of a 1 metre stick held out horizontally, to stop it from turning downwards the turning force you have to supply is the mass x gravity x distance
so here 1x9.8x1 = 9.8Nm..
go try it, get a 1 m stiock and sticky tape a 1L bottle of water at the end and try to hold it up 
in a car, it is a measure of the turning force, so if a motor with 100Nm was turning a 1m stick, it could move about 10kg...
try looking www.howstuffworks.com
Cya, Stewart
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Location:
adelaide
Registered:
May 2003
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Re: TORQUE
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Sat, 21 June 2003 08:48
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how ever confusing that was, it was interesting... my theory if you dont know dont ask... saves alot of confusion... all i know is that on gt3 my rz supra has like 120 somthings of torque and that really helps to get it sideways and bag up...
so in conclusion torque is fun...
shane
p.s. if u could explain it a more eaiser term i would apreciate (?)it...
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Sat, 21 June 2003 08:49
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so i'm guessing 545Nm of torque out of my V8 TA22 is pretty good then?
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Location:
Sydney
Registered:
May 2002
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Re: TORQUE
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Sat, 21 June 2003 08:51
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i Know u lose power through a drivetrain ..... but do u also lose torque ?
never thought about that
Thanx
Mani
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Location:
Canberra
Registered:
September 2002
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Re: TORQUE
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Sat, 21 June 2003 09:52
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| oldcorollas wrote on Sat, 21 June 2003 17:20 |
easy as man,
1 newton metre (Nm) mean that you have a 1 metre stick with 1 newton of force at the end. a newton is the mass multiplied by gravity...
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Force = mass*acceleration, not mass*gravity
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Location:
Brisbane
Registered:
May 2002
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Re: TORQUE
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Sat, 21 June 2003 12:29
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[/quote]
Force = mass*acceleration, not mass*gravity[/quote]
So you want me to believe that Gravity isn't an acceleration of approx 9.8 meters per s per s (ms-2)? he he
If I drop something does it accelerate? Yep (untill it gets to terminal velocity anyway) due to gravity, gravity is a form of acceleration.
Cheers
Wilbo
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Sat, 21 June 2003 13:06
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ok guys, look.... i didn't ask for a science lesson, but thanks for the great response (as confusing and argumentative as it is).
Can anyone explain it to me as if they were explaining it to their girlfriends?
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Location:
Sydney
Registered:
May 2002
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Sat, 21 June 2003 13:12
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that helps heaps mani....thanks dude.
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Location:
MACKAY
Registered:
May 2002
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Re: TORQUE
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Sat, 21 June 2003 13:20
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| BAD22 wrote on Sat, 21 June 2003 23:06 |
ok guys, look.... i didn't ask for a science lesson, but thanks for the great response (as confusing and argumentative as it is).
Can anyone explain it to me as if they were explaining it to their girlfriends?
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Tell them it's something they do to much !!!
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Location:
was adelaide now newcastle
Registered:
February 2003
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Re: TORQUE
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Sat, 21 June 2003 22:52
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i Know u lose power through a drivetrain ..... but do u also lose torque ?
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from what i know the gearing of a drive train will actually increase torque at the wheels, like the long spanner undoing the nut you have described.
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Location:
Launceston, Tasmania
Registered:
May 2002
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Re: TORQUE
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Sat, 21 June 2003 23:17
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| manipulate wrote on Sat, 21 June 2003 23:10 |
put simply.....when your undoing a bolt.....if its really tight.....u get a longer spanner....hence increasing how much torque u have through gearing
thats one way of looking at it
but with a longer spanner, u cant spin it too fast.....so u lose power as u "rev"....
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not sure if i'm on the right track but does this mean that if i got bigger wheels i would have more torque? and less power?
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Location:
Sydney
Registered:
May 2002
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Re: TORQUE
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Sun, 22 June 2003 01:55
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not neccesarily
when your changing gearing.....its not always bigger does this and smaller does this
eg: have u ever ridden a mountain bike ?......the larger the cogs/sprockets whatever u want to call them are at the back where the wheel is.....the 'lower' the gear u have.......
where as the larger the cogs/sprockets are at the front the 'higher' gear u have
it depends where in the setup your changing gearing
understand ?
if u have bigger wheels on a car, 1 revolution of the wheel is now a longer travelling distance right ?
what do u think .....do u think this is gonna be good for low down torque ?
Ta
Mani
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: TORQUE
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Sun, 22 June 2003 02:18
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| trent_kershaw wrote on Sat, 21 June 2003 19:52 |
Force = mass*acceleration, not mass*gravity
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Gravity is more specifically the acceleration derived by the mass of the earth. This is measured as ~9.81 m/s^2 at 'sea level' (in fact, 'sea level' is a predefined distance from the centre of the earth). You will notice with just a cursory glance at the defining SI units that it is acceleration. A Newton (what oldcorollas was defining) is defined as mass multiplied by the accelerative force of the eart at sea level. Oldcorollas stands corrected.
BAD22, unfortunately (for you), the definition of torque requires a reasonable command of some basic Year 9 physics. If you don't want a 'science lesson', I suggest you stick to doing some humanities style subjects and drinking lattes with your chardonnay socialist friends in some oohlala cafe in an inner city suburb discussing post modernist whaling in the North Sea. If you cannot grasp 'oldcorolla's' basic yet excellent explanation, then you are beyond help. Harsh but true.
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Registered:
June 2003
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Re: TORQUE
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Sun, 22 June 2003 11:26
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I would have thought that seen this is about flywheels, and rotating bodies that the sum of torque (sigmaT) would equal the moment of inertia (I) multiplied by the angular acceleration (alpha)
Giving T=Ia the first thing you'll learn in mechanical engineering. Seen a flywheel has a set moment of inertia (lets say that it's a perfect disc) this would be the radius squared x the mass x root 2, then the only thing that can change the acceleration is how much force your engine is applying to spin the wheel and give it acceleration the more torque, the faster you can spin the wheel.
That probably didn't make much sense but hey, work it out if you have large torque and a light flywheel T/I=a then you'll have more acceleration then someone who has the same torque but a much heavier flywheel. (simple fractions) 
Cheers,
Charlie.
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Sun, 22 June 2003 15:58
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Maybe there should be a forums section for dummies, what do u reckon gianttomato?
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: TORQUE
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Mon, 23 June 2003 01:05
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Not at all. I just find it amusing that people that people might want a non scientific explanation for a scientific principle. Poorly conceptualised analogies only create more confusion.
As for torque loss, the very nature of gearing implies that torque is multiplied. However if one could have true 1:1 gearing, then given that no system is 100% efficient, torque must be lost.
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Registered:
June 2003
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Re: TORQUE
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Mon, 23 June 2003 08:06
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Put simply, you lose torque from your flywheel because of bearing fricton and all the normal kinds of friction. Also less torque is going through the wheels because that requires spinning more things.
that better?
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Mon, 23 June 2003 10:00
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dudes.....u guys are getting so caught up in trying to prove each other wrong(or right)that u are straying from my initial question.
IS THERE ANYONE OUT THE THAT CAN EXPLAIN IN ENGLISH THE WHOLE Nm THING? WHAT IT MEANS AND HOW IT IS MEASURED?
If i want an explanation directly out of a text book, i'll ask Tomato head over there.
I know what Torque is. I just wanna know how other people would explain it because other people might have a simpler explanation that my Fiance(pilot of BAD22) would understand.
SO TOMATO, GO STICK YOUR HEAD UP YOUR ASS. 
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Location:
sydney
Registered:
December 2002
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Re: TORQUE
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Mon, 23 June 2003 19:37
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| gianttomato wrote on Sun, 22 June 2003 12:18 |
BAD22, unfortunately (for you), the definition of torque requires a reasonable command of some basic Year 9 physics. If you don't want a 'science lesson', I suggest you stick to doing some humanities style subjects and drinking lattes with your chardonnay socialist friends in some oohlala cafe in an inner city suburb discussing post modernist whaling in the North Sea. If you cannot grasp 'oldcorolla's' basic yet excellent explanation, then you are beyond help. Harsh but true.
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garbage.
all BAD22 needs to know in the way of concepts, is that torque = twist. "Nm" simply represents a newton (unit of force, like kg) acting at the end of a given distance, in this case 1 metre. this was all covered in previous posts above. its simple leverage, not rocket science. more force at the end of the metre, more twist, more torque.
on a side note: torque is often mistaken by those with little or no grasp on the relevent concepts as being more important than power. usually by the same group of people, oddly enough, who think turbos are for small engines only, and/or inferior to superchargers. but i digress. power is what moves a car or object. so what is power? power is work done over time. to understand that you must understand that torque is 1-dimensional; by which i mean you can have torque with zero motion taking place. ie by leaning on a spanner on a jammed nut or bolt, or holding the armature of a small electric motor tightly between your fingers and attaching a battery. if said spanner is a foot long, and you apply 40 pounds of force, youre applying 40ft/lbs of torque to the nut or bolt youre trying to undo/tighten. if it doesnt move, no work is taking place. the second that nut moves, work has been done. power is thus torque x rpm.
back to the electric motor. if you have an electric motor that generates 1Nm of torque @ 1000rpm and the same 1Nm at 20,000rpm, it will be making 20 times the power it makes at 1000rpm, even thuogh the torque has stayed the same.
as for how newton meters are measured, the only realistic way to measure them (in the automotive sphere of things anyway) is via an engine dyno. chassis dynos measure torque at the wheels, and spit out a (torque) figure which is the result of the cars gearbox and differential. power is calculated from referencing the roller speed against the torque measured at the rollers. this is commonly called tractive force, or effort, at least on a dyno dynamics eddy current dyno. on a dynojet inertial dyno the machine measures hp and calculates a guestimate of torque at the flywheel using inputted data on drivetrain gear ratios.
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Location:
Melbourne
Registered:
April 2003
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Re: TORQUE
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Tue, 24 June 2003 01:57
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Thank u Rusty. 
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE
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Tue, 24 June 2003 07:17
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i had hoped that the concept of torque being a twisting force was already known..... since most ppl who have changed a head gasket have encountered the 'torque' required for their headbolts... seems i was drastically mistaken.
it's not rocket science, btu if someone can't extrapolate from the concept of a force acting at a distance, resulting in a circular motion, to gearing and force at wheels... not much i can do....
www.howstuffworks.com
as for torque not being important? you tell only half the story...
"on a side note: torque is often mistaken by those with little or no grasp on the relevent concepts as being more important than power. usually by the same group of people, oddly enough, who think turbos are for small engines only, and/or inferior to superchargers. "
i think a review of the concepts is in order.
two cars with same size tyres, one with twice the torque at the wheels at the same car speed, and thus twice the force at the tyres circumference acting on the road..... you tell me which one is going to accelerate faster ( A = F/M)
the power issue is misinterpreted by many ppl to be most important. a famous quote(and i can't even remember who said it now..) was "power sells cars, torque wins races" and that is true.
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.
take F1 cars as an example. they are what? 3L motors? they have a theoretical MAXIMUM torque that can be produced from 3L capacity (see my equations thread). BUT, they rev to sayy... 15000rpm. if you have a normal 3L motor running at 5000rpm and an F1 3L motor running at 15000rpm, both are at 100% volumetric efficiency, THEY WILL BOTH BE MAKING THE SAME TORQUE.
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.
this is why ppl think that a car with more power accelerates faster than a car with more torque.
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.
"power is what moves a car or object"
ahhh, i believe Newton had something to do with explaining this.... something about FORCE  ? google for Newtons laws, i can't be bothered typing it.
power is the rate at which that force is applied.
an eddy current dyno is basically an electric motor. you feed anough electrical POWER into this motor so you can create enough reatrding FORCE so that you keep the engine rpm constant (we ain't getting into ramp rates here), as the motor is not held rigid, this causes the electric motor to ROTATE, and the FORCE required to stop this movement is what is measured, and is calibrated against a known FORCE at the rollers.
i was hoping that by using the semi-scientific analogy of
"1 kilogram at the end of a 1 metre stick held out horizontally"
would avoid trying to explain that a 'newton metre' is a 'moment of force' and what bending moments are and haviong to explain the whole damn SI system..... (to ppl wanting a 'girlfiends explanation)
to cap it all off. PLEASE look at these HOW stuff works pages as it will save much bother and typing in the future
How Force, Power, Torque and Energy Work
http://science.howstuffworks.com/fpte.htm
How do you convert engine torque to horsepower?
http://auto.howstuffworks.com/question622.htm
How Horsepower Works
http://auto.howstuffworks.com/horsepower.htm
How Gears Work
http://science.howstuffworks.com/gear.htm
| rusty wrote on Tue, 24 June 2003 05:37 |
all BAD22 needs to know in the way of concepts, is that torque = twist. "Nm" simply represents a newton (unit of force, like kg) acting at the end of a given distance, in this case 1 metre. this was all covered in previous posts above. its simple leverage, not rocket science. more force at the end of the metre, more twist, more torque.
on a side note: torque is often mistaken by those with little or no grasp on the relevent concepts as being more important than power. usually by the same group of people, oddly enough, who think turbos are for small engines only, and/or inferior to superchargers. but i digress. power is what moves a car or object.
back to the electric motor. if you have an electric motor that generates 1Nm of torque @ 1000rpm and the same 1Nm at 20,000rpm, it will be making 20 times the power it makes at 1000rpm, even thuogh the torque has stayed the same.
as for how newton meters are measured, the only realistic way to measure them (in the automotive sphere of things anyway) is via an engine dyno. chassis dynos measure torque at the wheels, and spit out a (torque) figure which is the result of the cars gearbox and differential. power is calculated from referencing the roller speed against the torque measured at the rollers. this is commonly called tractive force, or effort, at least on a dyno dynamics eddy current dyno. on a dynojet inertial dyno the machine measures hp and calculates a guestimate of torque at the flywheel using inputted data on drivetrain gear ratios.
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Location:
sydney
Registered:
December 2002
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Re: TORQUE
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Tue, 24 June 2003 08:33
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| 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.
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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.
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.
| oldcorollas wrote on Tue, 24 June 2003 17:17 |
the power issue is misinterpreted by many ppl to be most important. a famous quote(and i can't even remember who said it now..) was "power sells cars, torque wins races" and that is true.
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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?
| 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.
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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.
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clearly power is accelleration, not torque. you even said it yourself.
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.
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE
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Tue, 24 June 2003 09:32
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| 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.
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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.
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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.
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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?
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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.
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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.
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clearly power is accelleration, not torque. you even said it yourself.
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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.
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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
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Location:
sydney
Registered:
December 2002
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Re: TORQUE
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Tue, 24 June 2003 10:29
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dear oh dear, where to begin?
| 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.
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try reading this a few times and then try to realise the implications of it. it is, afterall, something you wrote yourself. allow me to highlight a particular relationship for you;
"identical power" ...
"accelerate at the same rate".
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
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?
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this is becoming quite amusing. another instance of the same thing. you went all the way through that, yet yourself still failed to recognise that youre taking about an f1 car making around 3 times the power of a 3 litre road car (yet similar torque, according to you). are you getting the point yet? or is it still slipping by? i suspect it may be, so let me again highlight the pertinent aspects of your own words for you;
"F1 has 3 times power because of higher rpm."
"F1 car acclerates 3 times faster."
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
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 .
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correct.
now allow me to pose an alternative question. one engine with 500lb/ft of torque and only 100hp, another engine with 500hp but only 100lb/ft of torque. both engines in two completely identical cars, with the only exception being gearing, any gearing being allowed. you tell me which car will be quicker. if you still think its car a, im afraid there is no hope for you.
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
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...
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ahh! those lazy engineers! shame on them. unfortunately, i dont think thats the case. engineers use numbers all the time i dont think they would care for your reason above, just as they wouldnt care for your whole argument.
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
sure power is a convenient way to measure motors, but it really doesn't mean that much.
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now thats really quite funny. i will have to keep that in mind. what an absolute gem.
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
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.
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this is good. however the first part (and i quote again; "the TORQUE an engine makes and the ENGINE SPEED (rpm) that it makes it at") equals power. funny that.
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
LOL, you have nfi.
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| oldcorollas wrote on Tue, 24 June 2003 19:32 |
i apologise to the people who did not turn off the 'email notification' of this thread, but i hate when ppl propogate half truths.
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oh really?
youre a pretty funny guy. i just want you to know i dont take any offence to what youve written, though i would be quite justified in doing so. but its going to be even more funny when you realise, whether today, tomorrow or a year from now, how you have been wrong from the get-go. you do not yet understand the concept of power. fix that and this disagreement will cease to exist.
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On Probation
Location:
North East NSW
Registered:
December 2002
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Re: TORQUE
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Tue, 24 June 2003 11:04
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this is the funniest shit i've ever read
bigger wheels make your car make more torque, quick everyone go out and buy chrome 19s!!!
well said tomato, people who can't do their research themselves shit me to tears. SO for all the stupid cocks out there who don't understand basic scientific and engineering principles, stop wasting time on forums about better things and do some research YOURSELVES for a fucking change! allow me to share a little secret with you, its a site that will tell you alot about most things you want to know about, you can find this ultra special super secret webpage at www.google.com
as for this little shitfight, i think you should both transform into well fit, busty, bikini clad honeys and settle this the only way possible - jelly wrestling
you'll notice you are both arguing the same point, except one of you is expressing his argument in forms of torque, one in forms of power. you can argue until the cows come home about this sort of thing, the best one i ever had was a rather lengthy heat resistance vs pad wear discussion converning brakes
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE
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Tue, 24 June 2003 11:12
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| rusty wrote on Tue, 24 June 2003 20:29 |
"identical power" ...
"accelerate at the same rate".
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that;s the whole frickin point dude, wake up!!!
do some equations and get back to me
"F1 has 3 times power because of higher rpm."
"F1 car acclerates 3 times faster."
again, that's the whole point, if you gear a car to take advatage of the rpm at which it makes peak torque, you get gearing advantages.
| rusty wrote on Tue, 24 June 2003 20:29 |
now allow me to pose an alternative question. one engine with 500lb/ft of torque and only 100hp, another engine with 500hp but only 100lb/ft of torque. both engines in two completely identical cars, with the only exception being gearing, any gearing being allowed. you tell me which car will be quicker. if you still think its car a, im afraid there is no hope for you.
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LOL ROTFL
so you want me to take a car with 9.5hp (500lb/ft@100rpm)
and race you with a car with 500hp (100lb/ft@26260rpm
dude lay off the drugs, who the heck do you think would win???
i'm saying that if you had that 500hp 26260rpm monster of a motor (which by the way, would be a 740cc under 100% efficiency)
and raced me with a 100rpm motor with 26260lb/ft (which would be an ideal 196L motor), then we would have an even race....
this is because when all is said and done and you gear the motors down, they have the same torque at the rear axle and the same force at the tyres.
please get this idea. it hurts that you can't grasp it
| rusty wrote on Tue, 24 June 2003 20:29 |
this is good. however the first part (and i quote again; "the TORQUE an engine makes and the ENGINE SPEED (rpm) that it makes it at") equals power. funny that.
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well duh, that's what i've been saying all along.
how do you calculate the acceleration of anything? F=MA
how do you work out what the force at a tyre contact patch is? F=TQ/wheel radius
how do you work out axle torque?
engine torque x gearing.
but how do you work out power?
hp = ((lb/ft)xrpm/5252
or (lb/ft) = (hpx5252)/rpm
how do you work out power at rear axle
hp/gearing
tyre contact force,
F = (engine torque) x gearing/wheel radius
how do you work out power at rear axle
hp/gearing
lets take two motors with same power, one at 5000rpm, one at 10000rpm, the 10000rpm motor is geared at 2:1 compared to 5000rpm one
for 10000rpm
axle hp = hp/2
for 5000rpm
axle hp = hp
since (lb/ft) = (hpx5252)/rpm
for 10000rpm
lb/ft = (hpx2626)/rpm
for 5000rpm
lb/ft = (hpx5252)/rpm
now since
F = (engine torque) x gearing/wheel radius
for 10000rpm
F= (((hpx2626)/rpm) x 2)/wheel radius
F=((hpx5252)/rpm)/wheel radius
for 5000rpm
F= (((hpx5252)/rpm) x 1)/wheel radius
F=((hpx5252)/rpm)/wheel radius
and whoop de doo, they are the same. same force at tyre for same POWER, even tho the 10000rpm engne has half the torque as the 5000rpm one.... they still accelerate at the same rate
now please show me your calculations to disprove that two cars with identical POWER, but different TORQUE, when gearing is made to equal the top speed of both motors, will not have the same acceleration..
i dare you.. no i double dare you to brign those calculations to the forum, or even dyno day (if you will show up)
you can't accept that a motor with twice the torque but half the revs and half the gearing accelerates at the same speed as one with half the torque, double the revs and double the gearing...
fcs, i agree with you that more power = faster acceleration, but this does not happen unless you change gearing. and in the real world there are only a certain number of ratios you can choose. do you change you diff everytime you increase the rpm range of your motor? (i actually did when i cammed my 4K, i put a 4.33 instead of a 4.11, TO TAKE ADVANTAGE OF GEARING!!!)
please check the clacs above and show me how what i have said is incorrect from a mathematical standpoint.
Cya at the dyno day (i assume you are coming?)
Stewart
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: TORQUE
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Tue, 24 June 2003 11:46
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Arguing with an engineer is a bit like wrestling with a pig in mud. After a few hours, you work out they like it.
Shamelessly stolen from an engineer's sig.
I can see you are enjoying yourself oldcorolla!
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE
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Tue, 24 June 2003 12:01
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| gianttomato wrote on Tue, 24 June 2003 21:46 |
Arguing with an engineer is a bit like wrestling with a pig in mud. After a few hours, you work out they like it.
Shamelessly stolen from an engineer's sig.
I can see you are enjoying yourself oldcorolla!
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 how did you know
actually i'm a metallurgist, but i have more than a passing interest in designing, building and modifying motors, as the last few days posts attest i guess.....
just have to finish my damn PhD so i can put injection and Megasquirt on my rolla
first EFI KE15 in toymods?
Cya, Stewart
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
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Re: TORQUE
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Tue, 24 June 2003 12:27
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i would read this... but i don't want to
I already have a grasp of the concepts of force, torque and power. Thank god for my 91-100% ranking in HSC Physics 
Also makes me glad that i'm a studying Telecommunications Engineer.
So, anyone want to start an arguement about PGP vs X509?
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Location:
Canberra
Registered:
September 2002
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Re: TORQUE
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Tue, 24 June 2003 12:44
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Karl,
You must read this thread! Trust me, it's worth it!
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Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
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Re: TORQUE
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Tue, 24 June 2003 13:06
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i got through some of it... and decided against that after the argument against gravity being a force causing acceleration.
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Location:
Canberra
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September 2002
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Re: TORQUE
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Tue, 24 June 2003 14:03
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[quote title=trent_kershaw wrote on Sat, 21 June 2003 19:52
Force = mass*acceleration, not mass*gravity[/quote]
Is this the argument? If so, I just wasn't specific enough... I just meant that mass*gravity is only one case of force, whereas F=ma is the general formula.
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Location:
sydney
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December 2002
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Re: TORQUE
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Tue, 24 June 2003 16:35
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| oldcorollas wrote on Tue, 24 June 2003 17:17 |
that;s the whole frickin point dude, wake up!!!
do some equations and get back to me
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i dont need to "do equations and get back to you". lets have a look how this started;
| oldcorollas wrote on Tue, 24 June 2003 17:17 |
as for torque not being important? you tell only half the story...
| rusty wrote on Tue, 24 June 2003 05:37 |
on a side note: torque is often mistaken by those with little or no grasp on the relevent concepts as being more important than power. usually by the same group of people, oddly enough, who think turbos are for small engines only, and/or inferior to superchargers.
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i think a review of the concepts is in order.
two cars with same size tyres, one with twice the torque at the wheels at the same car speed, and thus twice the force at the tyres circumference acting on the road..... you tell me which one is going to accelerate faster ( A = F/M)
the power issue is misinterpreted by many ppl to be most important. a famous quote(and i can't even remember who said it now..) was "power sells cars, torque wins races" and that is true.
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lets not meander from the topic. the only logical interpretation of the above is that you think torque is more important than power, yet;
| oldcorollas wrote on Tue, 24 June 2003 19:32 |
hell, i'll even spell it out for you.
F1 has 3 times power because of higher rpm.
...
F1 car acclerates 3 times faster.
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and secondly;
| oldcorollas wrote on Tue, 24 June 2003 18:33 |
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.
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(and right after that...)
| oldcorollas wrote on Tue, 24 June 2003 21:12 |
| rusty wrote on Tue, 24 June 2003 20:29 |
this is good. however the first part (and i quote again; "the TORQUE an engine makes and the ENGINE SPEED (rpm) that it makes it at") equals power. funny that.
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well duh, that's what i've been saying all along.
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cant you see these are conflicting sentiments? they are mutually exclusive. you either go with one or the other. if you think torque is more important, fine. youre wrong, but thats less stupid than thinking both the above are right simultaneously.
you have an obsession with torque, when torque is only a component of power, the other part being the rate it is applied, or rpm. i said at the beginning that power is more important than torque, because obviously if you have the one, you have the other. yet you interjected to the contrary (above). that has been my disagreement with you from the start, and continues to be.
torque doesnt win races, matching the power curve to your gearing wins races. ie F1 - peaky high-rpm power, 7 speed close ratio boxes, and the ability to shift them in thousanths of a second.
repeat 3 times after me, power moves the car. not torque.
still disagree? with only torque, there is no motion component. as soon as motion occurs, work has been done and thus we are discussing power. by disagreeing with the above youre failing at simple interpretation of the very equations you keep trotting out.
| rusty wrote on Tue, 24 June 2003 20:29 |
now allow me to pose an alternative question. one engine with 500lb/ft of torque and only 100hp, another engine with 500hp but only 100lb/ft of torque. both engines in two completely identical cars, with the only exception being gearing, any gearing being allowed. you tell me which car will be quicker. if you still think its car a, im afraid there is no hope for you.
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| oldcorollas wrote on Tue, 24 June 2003 21:12 |
LOL ROTFL
so you want me to take a car with 9.5hp (500lb/ft@100rpm)
and race you with a car with 500hp (100lb/ft@26260rpm
dude lay off the drugs, who the heck do you think would win???
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no.
pay attention this time. i said;
one engine with 500lb/ft of torque and only 100hp
another engine with 500hp but only 100lb/ft of torque
who wins?
want to have another crack at it?
in case you didnt get the point, and it seems you didnt, this is to illustrate that power is more important than torque. which is what i said in my first post in this thread. if you had no disagreement with that then you shouldnt have responded to the contrary.
| oldcorollas wrote on Tue, 24 June 2003 21:12 |
now please show me your calculations to disprove that two cars with identical POWER, but different TORQUE, when gearing is made to equal the top speed of both motors, will not have the same acceleration..
i dare you.. no i double dare you to brign those calculations to the forum, or even dyno day (if you will show up)
you can't accept that a motor with twice the torque but half the revs and half the gearing accelerates at the same speed as one with half the torque, double the revs and double the gearing...
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you leading somewhere with this? what are you rambling about? why would i have any interest in proving this? try keeping it relevant, or at least respond to what i said.
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Location:
Hornsby, N.S.W
Registered:
September 2002
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Re: TORQUE
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Tue, 24 June 2003 21:08
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thanks for starting this one george, this is a very interesting thread!!!
justin
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Location:
Brisbane
Registered:
June 2003
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Re: TORQUE
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Tue, 24 June 2003 22:49
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so when torque exceeds the total amount of gravity + surface friction - the loss through the drive train = ... ??
wheel stand ??
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On Probation
Location:
North East NSW
Registered:
December 2002
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Re: TORQUE
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Wed, 25 June 2003 07:26
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standing around at work today i was thinking of this, and something rather amusing dawned on me. because i am not as eloquent as the gentlemen above, i steal my definitions from webpages:
from http://www.fordcobraengines.com/Horsepowerdefine.h tm
In James Watt's judgement, one horse can do 33,000 foot-pounds of work every minute. So, imagine a horse raising coal out of a coal mine as shown above. A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute, or 33 pounds of coal 1,000 feet in one minute, or 1,000 pounds 33 feet in one minute. You can make up whatever combination of feet and pounds you like. As long as the product is 33,000 foot-pounds in one minute, you have a horsepower.
so far this is all fact
NOW
as men aren't created equal, it goes to stand that neither are horses. depending on size, age, breed, conditions, food, lifestyle, upbringing (ie: all the things that make humans different too) you're going to get a horse that is weaker or stronger than another horse
so whilst theoretically, you have a horse that can move 330lb 100ft in 1min. however IF you get a good horse, it could maybe move 300lb 100ft in 50 seconds, or it could move 350lb 100ft in a minute, or it could move 330lb 120ft in a minute. and what does this give you?
a horse with more than one horsepower!!!
ahh isn't life a crackup
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE and shite stirring
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Wed, 25 June 2003 12:27
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rotfpmsl
man i don't think torque is better than power, i don't think power is better than torque, in fact i couldn't care less .
The only "theory" i have any 'sentiment' for is 'increasing efficiency', and i will extoll the virtues of that theory until i die 
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cant you see these are conflicting sentiments
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umm no i don't have any fuzzy feelings toward either... i don;t think they are conflicting either. it's like saying you can't like chocolate ice-cream because you don't like strawberry. you CAN like both!
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if you think torque is more important, fine. youre wrong, but thats less stupid than thinking both the above are right simultaneously
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fcol, there is no right or wrong, both power and torque are good and in different circumstances, more or less important, but it depends on which side of the equation you look at it,
fwiw, i bet my motor is smaller than yours  so who's got more torque?
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you have an obsession with torque, when torque is only a component of power, the other part being the rate it is applied, or rpm. i said at the beginning that power is more important than torque, because obviously if you have the one, you have the other. yet you interjected to the contrary (above). that has been my disagreement with you from the start, and continues to be.
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HA HA AH HA LOL..... without torque, you got no power. without motion you have no power. but torque is still there, moving or not. can ya say headbolts?
this is such funny shit . we are both arguing EXACTLY the same point, and then saying that either torque or power is important. you can use the same equations to prove both arguments the only difference is that power has a time component and torque doesn't. when it comes down to it, neither torque or power are important. what is important is the force at the road and the resulting acceleration. (and also efficiency and driveability, but that's another issue )
what i think is so funny, and why i responded to you in the first place is because you are adamant that power is the only important thing and that torque is not important. that's exactly the opposite idea that was espoused in that rotary thread, where everyone bitched and moaned because rotaries only have power and no torque i read that one with much mirth, but to see the rotary point of view come out again in another thread is quite amusing and also that the people who bagged rotaries, for not having torque, are also not jumping in on this..... actually they are prolly having too much fun watching
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lets not meander from the topic. the only logical interpretation of the above is that you think torque is more important than power,
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what? there was a topic? oh yeah, explain torque in a simple manner
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for example if you have 1 kilogram at the end of a 1 metre stick held out horizontally, to stop it from turning downwards the turning force you have to supply is the mass x gravity x distance
so here 1x9.8x1 = 9.8Nm
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the only logical interpretation is that i'm shit-stirring you, and at the same time trying to dispel the myth that power is the be-all and end-all. what do i think? i think all motors should rev to 9000+rpm and have close to 100% efficiency like the Honduh S2000 motor, and 1L bike engines. i like efficiency and high revs, not because of power and torque, but because i like power sliding around a corner at 8000rpm in my 1969 corolla!!!!!  whooosh!!!!!!!
heh heh, i think this is the first thread i ever hijacked.. and what fun it has been. i bid you adieu.
Cya at DD7, Stewart
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: TORQUE and shite stirring
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Wed, 25 June 2003 12:36
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one last thing
From WWW.HOWSTUFFWORKS.com
How Horsepower Works
by Marshall Brain
Chances are you've heard about horsepower. Just about every car ad on TV mentions it, people talking about their cars bandy the word about and even most lawn mowers have a big sticker on them to tell you the horsepower rating.
But what is horsepower, and what does the horsepower rating mean in terms of performance? In this edition of HowStuffWorks, you'll learn exactly what horsepower is and how you can apply it to your everyday life!
Definition
The term horsepower was invented by the engineer James Watt. Watt lived from 1736 to 1819 and is most famous for his work on improving the performance of steam engines. We are also reminded of him every day when we talk about 60-watt light bulbs.
The story goes that Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. He found that, on average, a mine pony could do 22,000 foot-pounds of work in a minute. He then increased that number by 50 percent and pegged the measurement of horsepower at 33,000 foot-pounds of work in one minute. It is that arbitrary unit of measure that has made its way down through the centuries and now appears on your car, your lawn mower, your chain saw and even in some cases your vacuum cleaner!
What horsepower means is this: In Watt's judgement, one horse can do 33,000 foot-pounds of work every minute. So, imagine a horse raising coal out of a coal mine as shown above. A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute, or 33 pounds of coal 1,000 feet in one minute, or 1,000 pounds 33 feet in one minute. You can make up whatever combination of feet and pounds you like. As long as the product is 33,000 foot-pounds in one minute, you have a horsepower.
You can probably imagine that you would not want to load 33,000 pounds of coal in the bucket and ask the horse to move it 1 foot in a minute because the horse couldn't budge that big a load. You can probably also imagine that you would not want to put 1 pound of coal in the bucket and ask the horse to run 33,000 feet in one minute, since that translates into 375 miles per hour and horses can't run that fast. However, if you have read How a Block and Tackle Works, you know that with a block and tackle you can easily trade perceived weight for distance using an arrangement of pulleys. So you could create a block and tackle system that puts a comfortable amount of weight on the horse at a comfortable speed no matter how much weight is actually in the bucket.
(fast horses? gearing with block and tackle.. hmmmm)
Horsepower can be converted into other units as well. For example:
1 horsepower is equivalent to 746 watts. So if you took a 1-horsepower horse and put it on a treadmill, it could operate a generator producing a continuous 746 watts.
1 horsepower (over the course of an hour) is equivalent to 2,545 BTU (British thermal units). If you took that 746 watts and ran it through an electric heater for an hour, it would produce 2,545 BTU (where a BTU is the amount of energy needed to raise the temperature of 1 pound of water 1 degree F).
One BTU is equal to 1,055 joules, or 252 gram-calories or 0.252 food Calories. Presumably, a horse producing 1 horsepower would burn 641 Calories in one hour if it were 100-percent efficient.
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I Supported Toymods
Location:
perth
Registered:
September 2002
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Re: TORQUE
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Wed, 25 June 2003 17:41
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super_jamie : i like your way of thinking dude! Man my engine is 132hp. . . but their good horses though.
I got a question for you two crazy people :
Can you explain the anomoly of the torque band. By this i mean, why does my engine produce max torque at ~2700rpm which descends with increasing rpm?
And how can you tune an engine to have more consistent flat torque figures? (like BMW, rally and shit)
Peace
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Location:
Brisbane
Registered:
May 2002
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Re: TORQUE
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Wed, 25 June 2003 22:37
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Your torque curve is determined by lots of things, but in a nutshell you'll get maximum torque at the rpm where you get maximum cylinder filling (ie closest to 100% volumetric efficiency). If you want to alter your torque curve, the easiest way to do it is change your cam profile to encourage higher VE at the desired rpm.
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Location:
Brisbane
Registered:
June 2003
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Re: TORQUE
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Thu, 26 June 2003 00:37
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BRAVO...
so technically, 1 horse with a 5 speed sadle and twin feed-bags on 16hands wheels = the equalivance of my car
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Location:
Melbourne
Registered:
June 2003
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Re: TORQUE
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Thu, 26 June 2003 01:58
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Torque is just turning power. The quicker in the rpm u reach peak torque the quicker peak turning power hits the road. In the automotive field, 4wd have huge torque figures. They have the ability, with less power to pull or tow huge weights, this is because of there "turning power". Therefore with the increase in power, the turning power will be the same, just the vehicle will be moving faster.
eq. 2 st162 celica's, both same power. one has less torque than the other. They both pull a trailer of 200kgs. which one would go faster to 100km/h?
the one with more torque
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Location:
Maroubra
Registered:
June 2002
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I Supported Toymods
Location:
perth
Registered:
September 2002
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Re: TORQUE
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Thu, 26 June 2003 05:49
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Look, i don't need a redefinition of torque dude, i think thats been covered. . .
Yeh, i understand maximum torque produced by engine is generally at maxiumum fill which is mainly determined by cam's and timing. And so for street cars, this is desireable at cruising speed rpm for best petrol economy, However :
---- Im still wondering how BMW and porsche engines have "iron flat" torque curves. How does an engine do this??
Cheers for any input (not redefinitions of torque!!!)
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: flat TORQUE curves
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Thu, 26 June 2003 06:23
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| bayka wrote on Thu, 26 June 2003 15:49 |
Look, i don't need a redefinition of torque dude, i think thats been covered. . .
Yeh, i understand maximum torque produced by engine is generally at maxiumum fill which is mainly determined by cam's and timing. And so for street cars, this is desireable at cruising speed rpm for best petrol economy, However :
---- Im still wondering how BMW and porsche engines have "iron flat" torque curves. How does an engine do this??
Cheers for any input (not redefinitions of torque!!!)
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cool, so you understand that the amount, or extent, of cylinder filling (commonly referred to as "volumetric efficiency") is directly related to the torque curve? (the VE and torque curve are almost mirror images, except for some mechanical loss as rpm increases)
so how do they get their "iron flat" torque curves? the flat torque curve reflects the VE curve, so by definition, the Beemer and porsche motors must have consistent cylinder filling (VE) over a wide range of rpm.
How do they do this?
by spending lots of money on cylinder head and intake tract development, with the end goal of having high volumetric efficiency over as wide a range of engine speeds possible.
also by having variable valve timing and lift, and many other gismos and gadgets (variable runner length etc).
basically what it comes down to is that they have a far more 'efficient' design.
is that what you wanted to know?
Cya, Stewart
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Location:
Cabramatta, NSW
Registered:
May 2002
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Re: flat TORQUE curves
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Thu, 26 June 2003 06:45
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Ah... I remember seeing this oldcorollas nick pop up with the name Stewart.
After seeing a few posts, I was wondering, could this be Stewart Ford? No, can't be, he disappeared off the face of the Earth.
But reading this thread, it's pretty much confirmed...
Where have you been dude? Good to see you back! Now I've gotta haul my arse to the dyno day to catch up!
Sorry, OT post.... Continue on with the flame war boys...
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: flat TORQUE curves
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Thu, 26 June 2003 07:03
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Heya Max,
yeah, i've been hiding for a while. basically got stuck at uni doing a PhD and never having enough car time  ...
up to? well, lots of K head development, finally built a new motor for the 15, 4K, hi comp, cam, d/d weber, made my own extractors, exhaust etc... had it at DD5, but it sure as hell goes a lot better now than the very first Toymods cruise... i remember trying to keep up with the supra boys and Phils GZE 30 coming up the hill from wisemans ferry... sliding around with positive camber and a near stock 4K ahh those were the days....
i have a full injection setup ready to go, have a couple of megasquirts to control it (have been organising group buys for them too), have K to T bellhousing and box ready to go, have designs for camber plates, brake upgrades, hilux diff etc... too much stuff... (and the wicked ideas, like DOHC and twin charge.. lets see what it takes to break a K crank )
just need to finish this damn thesis
DD7? i'll be looking forward to catching up with you and the 'ever busy' Mos then (i'll be seedy tho, got a ball to go to night before...)
kewl great to hear from ya man
Cya, Stewart
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