What exactly is torque
and is it good
and how do i increase it or will it not benefit me

SSS

Thanx

Oh, It will benefit, Yes it is good, And torque, Is what makes your car MOVE.

While I dont know the technical "Definition" of torque, basically, it is how quickly your car accelerates.

HP = Power
TQ = Acceleration

Machine torque
Torque is part of the basic specification of an engine: the power output of an engine is expressed as its torque multiplied by its rotational speed. Internal-combustion engines produce useful torque only over a limited range of rotational speeds (typically from around 1,000–6,000 rpm for a small car). The varying torque output over that range can be measured with a dynamometer, and shown as a torque curve. The peak of that torque curve usually occurs somewhat below the overall power peak. The torque peak cannot, by definition, appear at higher rpm than the power peak.

Understanding the relationship between torque, power and engine speed is vital in automotive engineering, concerned as it is with transmitting power from the engine through the drive train to the wheels. The gearing of the drive train must be chosen appropriately to make the most of the motor's torque characteristics.

Steam engines and electric motors tend to produce maximum torque at or around zero rpm, with the torque diminishing as rotational speed rises (due to increasing friction and other constraints). Therefore, these types of engines usually have quite different types of drivetrains from internal combustion engines.

Torque is also the easiest way to explain mechanical advantage in just about every simple machine.

[edit]
Relationship between torque and power
If a force is allowed to act through a distance, it is doing mechanical work. Similarly, if torque is allowed to act through a rotational distance, it is doing work. Power is the work per unit time. However, time and rotational distance are related by the angular speed where each revolution results in the circumference of the circle being travelled by the force that is generating the torque. This means that torque that is causing the angular speed to increase is doing work and the generated power may be calculated as:


Mathematically, the equation may be rearranged to compute torque for a given power output. However in practice there is no direct way to measure power whereas torque and angular speed can be measured directly.

Consistent units must be used. For metric SI units power is watts, torque is newton-metres and angular speed is radians per second (not rpm and not even revolutions per second).

[edit]
Conversion to other units
For different units of power, torque or angular speed, a conversion factor must be inserted into the equation. For example, if the angular speed is measured in revolutions instead of radians, a conversion factor of 2π must be added because there are 2π radians in a revolution:

, where rotational speed is in revolutions per unit time
Some people (e.g. American automotive engineers) use horsepower (imperial mechanical) for power, foot-pounds (lbf·ft) for torque and rpm's (revolutions per minute) for angular speed. This results in the formula changing to:


This conversion factor is approximate because the transcendental number π appears in it; a more precise value is 5252.113 122 032 55... It also changes with the definition of the horsepower, of course; for example, using the metric horsepower, it becomes ~5180.

Use of other units (e.g. BTU/h for power) would require a different custom conversion factor.

[edit]
Derivation
For a rotating object, the linear distance covered at the circumference in a radian of rotation is the product of the radius with the angular speed. That is: linear speed = radius x angular speed. By definition, linear distance=linear speed x time=radius x angular speed x time.

By the definition of torque: torque=force x radius. We can rearrange this to determine force=torque/radius. These two values can be substituted into the definition of power:


The radius r and time t have dropped out of the equation. However angular speed must be in radians, by the assumed direct relationship between linear speed and angular speed at the beginning of the derivation. If the rotational speed is measured in revolutions per unit of time, the linear speed and distance are increased proportionately by 2π in the above derivation to give:


If torque is in lbf·ft and rotational speed in revolutions per minute, the above equation gives power in ft·lbf/min. The horsepower form of the equation is then derived by applying the conversion factor 33,000 ft·lbf/min per horsepower:



Because 5252.113... = 33,000 / 2π.

provided by wikipedia ... http://en.wikipedia.org/wiki/Torque

torque is a circular force. an example of force is when you push a lawnmower. you create a force going in a straight line that pushes the lawnmower. Torque, is just force when you are relating it to a circle. For example, if you take the crankshaft in your motor and turn it, you are creating torque. The reason your wheels spin is because of torque. A force is being exerted on an object to create movement. I hope that made sense. Your best bet would be to just go to google.com and look up torque.

Machine torque
Torque is part of the basic specification of an engine: the power output of an engine is expressed as its torque multiplied by its rotational speed. Internal-combustion engines produce useful torque only over a limited range of rotational speeds (typically from around 1,000–6,000 rpm for a small car). The varying torque output over that range can be measured with a dynamometer, and shown as a torque curve. The peak of that torque curve usually occurs somewhat below the overall power peak. The torque peak cannot, by definition, appear at higher rpm than the power peak.

Understanding the relationship between torque, power and engine speed is vital in automotive engineering, concerned as it is with transmitting power from the engine through the drive train to the wheels. The gearing of the drive train must be chosen appropriately to make the most of the motor's torque characteristics.

Steam engines and electric motors tend to produce maximum torque at or around zero rpm, with the torque diminishing as rotational speed rises (due to increasing friction and other constraints). Therefore, these types of engines usually have quite different types of drivetrains from internal combustion engines.

Torque is also the easiest way to explain mechanical advantage in just about every simple machine.

[edit]
Relationship between torque and power
If a force is allowed to act through a distance, it is doing mechanical work. Similarly, if torque is allowed to act through a rotational distance, it is doing work. Power is the work per unit time. However, time and rotational distance are related by the angular speed where each revolution results in the circumference of the circle being travelled by the force that is generating the torque. This means that torque that is causing the angular speed to increase is doing work and the generated power may be calculated as:


Mathematically, the equation may be rearranged to compute torque for a given power output. However in practice there is no direct way to measure power whereas torque and angular speed can be measured directly.

Consistent units must be used. For metric SI units power is watts, torque is newton-metres and angular speed is radians per second (not rpm and not even revolutions per second).

[edit]
Conversion to other units
For different units of power, torque or angular speed, a conversion factor must be inserted into the equation. For example, if the angular speed is measured in revolutions instead of radians, a conversion factor of 2π must be added because there are 2π radians in a revolution:

, where rotational speed is in revolutions per unit time
Some people (e.g. American automotive engineers) use horsepower (imperial mechanical) for power, foot-pounds (lbf·ft) for torque and rpm's (revolutions per minute) for angular speed. This results in the formula changing to:


This conversion factor is approximate because the transcendental number π appears in it; a more precise value is 5252.113 122 032 55... It also changes with the definition of the horsepower, of course; for example, using the metric horsepower, it becomes ~5180.

Use of other units (e.g. BTU/h for power) would require a different custom conversion factor.

[edit]
Derivation
For a rotating object, the linear distance covered at the circumference in a radian of rotation is the product of the radius with the angular speed. That is: linear speed = radius x angular speed. By definition, linear distance=linear speed x time=radius x angular speed x time.

By the definition of torque: torque=force x radius. We can rearrange this to determine force=torque/radius. These two values can be substituted into the definition of power:


The radius r and time t have dropped out of the equation. However angular speed must be in radians, by the assumed direct relationship between linear speed and angular speed at the beginning of the derivation. If the rotational speed is measured in revolutions per unit of time, the linear speed and distance are increased proportionately by 2π in the above derivation to give:


If torque is in lbf·ft and rotational speed in revolutions per minute, the above equation gives power in ft·lbf/min. The horsepower form of the equation is then derived by applying the conversion factor 33,000 ft·lbf/min per horsepower:



Because 5252.113... = 33,000 / 2π.

provided by wikipedia ... http://en.wikipedia.org/wiki/Torque




Simple answer:

Horsepower is how much power you're making
Torque is what gets you down the track.

Basically, you can make 1000 horsepower all day long, but it doesn't mean squat if you don't have good torque to use that horsepower to get you down the road.

Damn fine detailed explanation though :twothumbs

Overly simple analogy of torque...

Imagine a 1 foot long wrench on say a lug nut. Put 200lbs on the end of that wrench. That lug nut is feeling 200 ft-lbs of torque (same as the advertised crank torque for the SS/SC).
OR
Imagine a 200 foot long wrench on the same lug nut with a 1 lb weight on the end. The result is the same 200 ft-lbs of torque on the nut.

Hope this helps.

Read this article.... http://vettenet.org/torquehp.html


And then this thread might help a bit more... http://www.*************/forums/showthread.php?t=1831&page=6&pp=10

Read this article.... http://vettenet.org/torquehp.html


And then this thread might help a bit more... http://www.*************/forums/showthread.php?t=1831&page=6&pp=10


Wow...

That Vette guy could not be MORE WRONG.

Another way of saying this is that a car will accelerate hardest at its torque peak in any given gear, and will not accelerate as hard below that peak, or above it. Torque is the only thing that a driver feels, and horsepower is just sort of an esoteric measurement in that context. 300 foot pounds of torque will accelerate you just as hard at 2000 rpm as it would if you were making that torque at 4000 rpm in the same gear, yet, per the formula, the horsepower would be *double* at 4000 rpm. Therefore, horsepower isn't particularly meaningful from a driver's perspective, and the two numbers only get friendly at 5252 rpm, where horsepower and torque always come out the same.

A car will accelerate hardest @ it's peak HP, not tq.....

Otherwise, cars would race in the RPM range with the highest TQ, and not over the RPM range with the highest average HP.

If peak TQ was the best point for racing, then this guy would never want to take his Cobalt SS/SC over 5000rpm, because torque falls off significantly after that point. However, peak HP comes AFTER 5000rpm because the TQ that IS there is being multiplied by the higher RPM's resulting in the range of the highest HP, the actual best rpm range for racing.

http://i15.photobucket.com/albums/a386/melissaco2003/DYNOCHARTview.jpg

Also, if you go by VetteGuy's suggestion that a car pulls harder @ peak tq no matter what the hp is, then that would mean that the Cobalt SS/SC would pull HARDER at 3000rpm than it does at 6000rpm because the tq is much higher, even though the car is making TWICE as much HP @ 6000rpm. Obviously, it is idiotic to suggest that the car pulls harder at 3000rpm than it does at 6000rpm. If you don't realize the stupidity of that suggestion already, go try it for yourself.



The point here is that HP is what really matters.

Based on this equation:

HP ~= (TQ*RPM)/5252

You can see that it takes either TQ OR RPMs to make good hp.


To conclude, I will quote myself from a previous post...

Torque is greatly misunderstood. Imagine 2 different cars, a Mustang and an S2000, for instance. But for now, lets assume that both have 260hp and weigh the same... basically adding a little weight and power to the S2k. Now, for arguments sake, we'll make some assumptions...

1. Both have LINEAR HP curves, which is not generally the case, but it is a generality

2. The GT makes peak 260hp @4500 rpm and the S2k makes peak 260hp @ 9000 rpm

3. Gearing and Aero is also the same

Now, in this case, because HP is merely a CALCULATION OF TQ and RPM, HP = TQ*RPM/5250 , both cars make the same HP, but the S2k has HALF the tq and TWICE the RPM at that point in order to make the SAME hp.

So, if the cars both weigh the same, have the same aerodynamics, same gearing, and same hp.... DESPITE the GT having TWICE as much TQ, they would be EQUALLY fast if both were at peak hp.

In fact, w/ both curves being linear, the cars would be EQUALLY FAST as long as the S2K kept TWICE the RPMS of the Mustang, and over the powerband that they use, the cars would have the SAME AREA UNDER THE CURVE, which is what really matters.

Essentially, TQ matters only as much as RPM matters. If you gear a car to stay in and use it's high rpm powerband, HP is what is important, not TQ.

Now, a car w/ more tq will be much faster at a given rpm, say @ 2000rpm. An S2000 would barely pull on a civic at that point, but the GT would have pletny of power. So, torquey cars have much more power for just cruising around outside of stratospheric rpms, BUT a car like the RSX-S or S2k can make up for that difference in TQ by using RPMs to multiply it to an equal HP rating.


Hopefully, this made sense. Essentially, HP and powerband (in the case of peaky tq curves and being unable to stay within them) are the most important factors in power output because TQ and RPM can both be made up for w/ more of the other.

Like I said, hopefully this was relatively clear and helps somebody and their understanding of HP and Torque... because they are very often misunderstood.

-Blainestang

Blaine...reread the article. He says horsepower is what matters. What he means by you will accelerate the hardest , is that you feel torque you don't feel horsepower. Meaning at peak torque you will feel like you are going the fastest, but it doesn't mean you are.

Blaine...reread the article. He says horsepower is what matters. What he means by you will accelerate the hardest , is that you feel torque you don't feel horsepower. Meaning at peak torque you will feel like you are going the fastest, but it doesn't mean you are.

The problem with that is that peak TQ doesn't actually "feel" faster than peak HP. (see S2000 example below)

Basically, this guy just makes it sound like he knows what he's talking about when he really doesn't.


Examples:


It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*."

WRONG. It's better to make torque at high rpm than low rpm, because THEN YOU MAKE MORE HP... and then you use gearing to take advantage of HP, not the other way around.


Any given car, in any given gear, will accelerate at a rate that *exactly* matches its torque curve

WRONG. Power curve is what matters... Torque Curve AND RPM's together dictate the power curve, not just the Torque curve alone.



Another way of saying this is that a car will accelerate hardest at its torque peak in any given gear, and will not accelerate as hard below that peak, or above it.

WRONG. The above Cobalt SS/SC accelerate hardest at max power, which is 1500rpms ABOVE the max TQ.



Torque is the only thing that a driver feels, and horsepower is just sort of an esoteric measurement in that context.

WRONG... effectively. Technically, you are feeling the Force, which is torque, but when that torque is being produced 4000 times per second (at 8000rpms), your car "feels" and IS a lot more powerful than if it that torque was being produced 1000 times per second (at 2000rpms)... because it's making more HP.

For example, I guarantee that an S2000 @ 9000rpm FEELS faster than a Mustang V6 at 2000rpm even though the V6 Mustang is making nearly DOUBLE the torque.

This is kind of a silly example and not exactly parallel because we aren't talking about moments and rotation, but bear with me........ Just imagine that you are standing on a skateboard and someone pushes you from behind with a FORCE of 50 lb. You'll go a little bit and then roll to a stop. Now, imagine that someone pushes you with 50 lb. of force 2000 times per minute. Every time someone pushes you with that force you will accelerate. The force is the same and that's what you're technically "feeling," but you will certainly "feel" like you are accelerating faster also because you are being accelerated 2000 times per minute instead of just once. Now, think about 4000 times per minute. You will accelerate TWICE as fast (eliminating wind resistance and stuff like that) because you are adding that force TWICE as often..... Hopefully that makes sense and the connection between the skateboard and a car can be seen.



300 foot pounds of torque will accelerate you just as hard at 2000 rpm as it would if you were making that torque at 4000 rpm in the same gear, yet, per the formula, the horsepower would be *double* at 4000 rpm.

:lol: WRONG... WRONG... WRONG.

Look at this S2000 Dyno...

http://www.dynoperformance.com/jpgraph/graph_hptq.php?ID=489&width=680&height=450

The Torque curve is pretty dang flat, so according to this VetteGuy, the S2000 accelerates just as hard at 3000 as it does at 8000rpm.

I mean, would anyone seriously be stupid enough to look at that graph and suggest that?

No, obviously the S2000 is accelerating MUCH harder @ 8000rpm than @ 3000rpm. Why? More HP... and not because of Torque, but because the miniscule torque is being multiplied by 8000rpm.

___________


Need I go on... the guy clearly makes his statements with confidence and makes them sound correct, but they are not. He is wrong on MOST of his points.

You are taking everything he is saying out of context. You have to read the whole thing.

The curve of the torque curve is determined by RPMs. So you are pushed back in your seat more in a Cobalt SS/SC at peak power then at peak torque? No. You are misunderstanding what he means when he says hard.

We both know that horsepower is more important, no reason to continue this.

You are taking everything he is saying out of context. You have to read the whole thing.

The curve of the torque curve is determined by RPMs. So you are pushed back in your seat more in a Cobalt SS/SC at peak power then at peak torque? No. You are misunderstanding what he means when he says hard.

We both know that horsepower is more important, no reason to continue this.


Yeah, a lot of it is probably semantics...

Either way, like you said, HP is what is ultimately important whether you get it from TORQUE or RPM, both of which don't mean anything without the other.

Yeah, a lot of it is probably semantics...

Either way, like you said, HP is what is ultimately important whether you get it from TORQUE or RPM, both of which don't mean anything without the other.
:twothumbs

you guys just confuse me

you guys just confuse me
How so? Because you are use to people saying... "Horsepower sales cars, torque wins races"??

you guys just confuse me

Let me know what you're confused about and I'll try to explain it better...

Isn't 15% the standard for drivetrian loss? If so, that S2000 is only 221hp at the crank!

you guys just confuse me

Maybe this will help you understand the concept a little better:

In simple terms, without getting technical, torque is the low end grunt of an engine, HP is the top end power.

So when you punch the gas at a low RPM in a V8 car and it pushes you back into the seat and pulls hard - thats torque.

When you're driving a Honda S2000 and you punch it at a low RPM, nothing happens. The engine bogs and starts to slowly accelerate. Once you get into the powerband though, usually around 6,000RPM, it starts to pull hard - thats Horsepower.

Both HP and Torque coexist throughout the rev range of an engine, but in general torque is more important in the low RPM's while HP is more important in the higher RPM's. Torque is a measurement of the power of an engine, while Horsepower is a measurement of how much work that torque can do at any given RPM.

Hope that helps.

Maybe this will help you understand the concept a little better:

In simple terms, without getting technical, torque is the low end grunt of an engine, HP is the top end power.

So when you punch the gas at a low RPM in a V8 car and it pushes you back into the seat and pulls hard - thats torque.

When you're driving a Honda S2000 and you punch it at a low RPM, nothing happens. The engine bogs and starts to slowly accelerate. Once you get into the powerband though, usually around 6,000RPM, it starts to pull hard - thats Horsepower.

Both HP and Torque coexist throughout the rev range of an engine, but in general torque is more important in the low RPM's while HP is more important in the higher RPM's. Torque is a measurement of the power of an engine, while Horsepower is a measurement of how much work that torque can do at any given RPM.

Hope that helps.
No... have you not read anything we have been saying?

I will give it a shot for you, remember this is extremely simplified;

Power = torque times velocity. The formula is not that complex, but to make it easier, it simplifes to: Horsepower=torque times RPM divided by 5252 once the constants are multiplied out.

So you have HP = torque*RPM/5252

So if your car makes 200 ft*lbs of torque at 2000 RPM, you get Power (aka horsepower) = 200*2000/5252 or 76 HP. This is the force that accelerates your vehicle (ignoring all drivetrain losses/wind resistance/etc.)

Now, lets say that you are running at 5500 RPM where the car is making 150 ft*lbs of torque. The power available to accelerate your vehicle is 150*5500/5252 or 157 horsepower. Again ignoring all the factors that bleed off net power available to accelerate the car, you are obviously going to accerate faster with just over twice as much power being generated.

The formula is why all internal combustion engines have the torque curve intersect the horsepower curve at 5252 RPM. Go ahead and plug in any torque number in the formula, use that 5252 RPM and see what you get for horsepower.

No... have you not read anything we have been saying?

Please tell me how thats wrong.

Like I said, it wasn't in technical terms, just plain English.

Please tell me how thats wrong.

Like I said, it wasn't in technical terms, just plain English.

Horsepower is the most important through out the RPM range unless we are talking about tractor pulls. ;)

Look at this S2000 Dyno...

http://www.dynoperformance.com/jpgraph/graph_hptq.php?ID=489&width=680&height=450

The Torque curve is pretty dang flat, so according to this VetteGuy, the S2000 accelerates just as hard at 3000 as it does at 8000rpm.

I mean, would anyone seriously be stupid enough to look at that graph and suggest that?

No, obviously the S2000 is accelerating MUCH harder @ 8000rpm than @ 3000rpm. Why? More HP... and not because of Torque, but because the miniscule torque is being multiplied by 8000rpm
Need I go on... the guy clearly makes his statements with confidence and makes them sound correct, but they are not. He is wrong on MOST of his points.

Actually, he is not. You appear to be confusing the rate of change in the power made (acceleration) with the rate of change in the speed of the vehicle.

My previous post showed why the vehicle will change its rate of speed more as power increases regardless of the torque made.

The slope of the horsepower curve will increase as the peak torque increases, decrease when the torque curve decreases and show a maximum slope at the torque peak. It is hard to see on this dyno, but if you see where the torque peak is, you will notice that the slope of the horsepower curve is at its maximum. As the torque drops off, the power increases because of the velocity increase more than offsets the lower torque, but the rate of change is less. Boils down to this: at the torque peak, the acceleration is at maximum, for every extra RPM there will be the greatest change in horsepower. That means that on a motor that peaks torque at 3500 RPM might show an increase of 35 horsepower from 3000-3500 RPM and another 35 horsepower from 3500-4000 RPM. That same engine might show a gain of 28 horsepower from 4000-4500 RPM and a gain of 24 horsepower from 4500-5000 RPM. The car will go faster with the higher horsepower as that is a measurement of the force (ignoring mass, as it is the same car), but the rate of the change follows the torque curve.

Now go back and substitute the word 'acceleration' for the phrase 'rate of change' as that is the definition of acceleration.

The greatest acceleration is experienced at the torque peak. Imagine a tach that goes to, say 10,000 RPM. On the CSS you jump on the gas in neutral. The tach moves up toward the torque peak, it starts off (relatively) slowly and moves faster as it climbs up towards the torque peak. At that peak, the needle is accerating as fast as it ever will. Once past the torque peak, it will still climb, but the needle is now moving slower. It is accerating more slowly. When the CSS runs out of boost and cam/heads the torque takes a huge nosedive. The horsepower is still there, the car has a lot of power to change its rate of speed, but the tach needle now starts to crawl upward, much more slowly accelerating than at the torque peak. You are now at 7000 RPM, ignoring PCM restraints/valve spring limits and such, your car is making pathetically low torque and the horsepower curve is starting to drop off. It is still making more power than it was at torque peak, but the acceleration is almost nonexistant.

Hope that clears up the confusion over the term acceleration. A very common miscommunication between folks.

Also, the huge jump in torque/power needs to be ignored here. That slope is not a true indication of what it going on. Some sort of intake butterfly or some other trickery pumps the torque up at that instant and it should show as a break and a jump in the curve, not connecting those two points. You need to look at the actual torque peak and look at the slope of the horsepower curve at that point only. It would be easier to see if you can get a more traditional dyno plot, especially one with a very peaky (non-flat) torque curve.

Actually, he is not. You appear to be confusing the rate of change in the power made (acceleration) with the rate of change in the speed of the vehicle.

My previous post showed why the vehicle will change its rate of speed more as power increases regardless of the torque made.

The slope of the horsepower curve will increase as the peak torque increases, decrease when the torque curve decreases and show a maximum slope at the torque peak. It is hard to see on this dyno, but if you see where the torque peak is, you will notice that the slope of the horsepower curve is at its maximum. As the torque drops off, the power increases because of the velocity increase more than offsets the lower torque, but the rate of change is less. Boils down to this: at the torque peak, the acceleration is at maximum, for every extra RPM there will be the greatest change in horsepower. That means that on a motor that peaks torque at 3500 RPM might show an increase of 35 horsepower from 3000-3500 RPM and another 35 horsepower from 3500-4000 RPM. That same engine might show a gain of 28 horsepower from 4000-4500 RPM and a gain of 24 horsepower from 4500-5000 RPM. The car will go faster with the higher horsepower as that is a measurement of the force (ignoring mass, as it is the same car), but the rate of the change follows the torque curve.

Now go back and substitute the word 'acceleration' for the phrase 'rate of change' as that is the definition of acceleration.

The greatest acceleration is experienced at the torque peak. Imagine a tach that goes to, say 10,000 RPM. On the CSS you jump on the gas in neutral. The tach moves up toward the torque peak, it starts off (relatively) slowly and moves faster as it climbs up towards the torque peak. At that peak, the needle is accerating as fast as it ever will. Once past the torque peak, it will still climb, but the needle is now moving slower. It is accerating more slowly. When the CSS runs out of boost and cam/heads the torque takes a huge nosedive. The horsepower is still there, the car has a lot of power to change its rate of speed, but the tach needle now starts to crawl upward, much more slowly accelerating than at the torque peak. You are now at 7000 RPM, ignoring PCM restraints/valve spring limits and such, your car is making pathetically low torque and the horsepower curve is starting to drop off. It is still making more power than it was at torque peak, but the acceleration is almost nonexistant.

Hope that clears up the confusion over the term acceleration. A very common miscommunication between folks.


Actually, acceleration (rate of change in velocity) is at it's maximum at maximum hp and acceleration is still high once the hp starts dropping off. However, when hp begins to drop off, the "jerk" (rate of change of acceleration) is actually negative because acceleration, though still higher than points with less power, is becoming smaller and smaller.

If it were true that maximum acceleration was at max torque, then people would shift way before redline in order to have the highest average tq, not hp, which is not the case.

Actually, acceleration (rate of change in velocity) is at it's maximum at maximum hp and acceleration is still high once the hp starts dropping off. However, when hp begins to drop off, the "jerk" (rate of change of acceleration) is actually negative because acceleration, though still higher than points with less power, is becoming smaller and smaller.

If it were true that maximum acceleration was at max torque, then people would shift way before redline in order to have the highest average tq, not hp, which is not the case.

If possible you do want to shift so that your RPMs drop to where they are at or just before your peak torque. That is what vetteguy meant when he said it is better to make torque higher to take advantage of gearing.

Actually, acceleration (rate of change in velocity) is at it's maximum at maximum hp and acceleration is still high once the hp starts dropping off. However, when hp begins to drop off, the "jerk" (rate of change of acceleration) is actually negative because acceleration, though still higher than points with less power, is becoming smaller and smaller.

If it were true that maximum acceleration was at max torque, then people would shift way before redline in order to have the highest average tq, not hp, which is not the case.

This is incorrect. You seem to again be confusing acceleration with power generated.

Acceleration is at its maximum at the torque peak. That is not where the car makes the most power however. The point where the car makes the most power is the horsepower peak. The car has the most excess power (beyond what it takes to offset wind drag/other losses) at that point and that excess power will increase the speed of the vehicle. The best point to shift is when the RPM drop from the gearing will end up at a point on the horsepower curve that is equal to the horsepower at the instant before the shift. This gives the highest average horsepower (highest average power). Most cars do best at redline in first gear, but that may differ in that, or any other, gear. Depends on the power curve and the gearing. Even at redline, first gear is usually so wide that it drops it to a point where less power is available than at redline.

Perhaps it will help to think of it this way; The engine will rev fastest at/around its torque peak. Go drive a manual transmission car with a tach. Put in in second gear at 1500 RPM and stomp on the gas. You will see the tach needle slowly move (accelerate), note where it picks up speed and moves the fastest, then it will slow down (rate of increase will lessen) as you increase RPM. If it happens too quickly in second gear to notice, try 3rd.

Hopefully I have not muddied the waters further and it makes more sense.

edit below;
The horsepower rate of change is highest at the torque peak. That is when the car will 'feel' fastest as it is pushing the car the hardest. That is the highest acceleration, it is an instantaneous condition. The car will change velocity faster at the horsepower peak, because, even though there is less torque and it is being pushed less hard, it is being pushed more often (RPM). More total force is available to move the car.

I think that is the confusion between us. Acceleration is not over time, it is at one particular instant in time. The power generated is essentially how many times that acceleration is applied to the car.

Look at this S2000 Dyno...

http://www.dynoperformance.com/jpgraph/graph_hptq.php?ID=489&width=680&height=450


Wow look at that peaky POS! :lol:

Is there any usuable power in that car? I'm assuming that is one of the older S2000's.

Acceleration is at its maximum at the torque peak. That is not where the car makes the most power however.

OK, so HERE you say that Acceleration is at it's maximum at maximum TQ...

The car will change velocity faster at the horsepower peak, because, even though there is less torque and it is being pushed less hard, it is being pushed more often (RPM). More total force is available to move the car.

But here (knowing that (change in velocity) / (change in time) = acceleration), you are saying that "The car will ACCELERATE faster at the horsepower peak"


However, I do think I see what you are saying, and technically, we are both correct. You are correct in the fact that INSTANTANEOUS Acceleration is at a maximum when the peak torque turns the crank, but the greatest acceleration over a time period is at the range where hp is greatest.

Make sense?

Horsepower is the most important through out the RPM range unless we are talking about tractor pulls. ;)


And what if we are?? :lol: :lol: :lol:

to add a little fuel to the fire....

Whats does a 500hp, 700hp, and 900hp Toyota Supra have in common? They all run 12's.

horsepower bench racing is great for dyno queens.

Torque wins races, pure & simple.

to add a little fuel to the fire....

Whats does a 500hp, 700hp, and 900hp Toyota Supra have in common? They all run 12's.

horsepower bench racing is great for dyno queens.

Torque wins races, pure & simple.

:rolleyes: Torque only wins racing in tractor pulls. Pure & simple.

What are the two fastest drag radialed cars? Oh a supra and mustang 5.0. 7.8-9s on drag radials.

And what if we are?? :lol: :lol: :lol:

Have you ever watched tractor pulls??? SOOOO... awesome!

Tractor Pulls kick all ass! Farm boy here, So, Naturally a fan!

Finally something we can agree on!!!

Torque wins races, pure & simple.

False, pure and simple.

Torque isn't worth jack without RPMs, and RPMs aren't worth jack without Torque.


HP is what matters and...

HP = TQ*RPM / 5252

So, if you have a lot of torque, but you can't rev, you're still going to have no HP. And if you have enough RPM's you don't even need a lot of TQ to win races... like the S2000.

"horsepower is how fast you hit the wall, torque is how far you take it with you."

But here (knowing that (change in velocity) / (change in time) = acceleration), you are saying that "The car will ACCELERATE faster at the horsepower peak"


However, I do think I see what you are saying, and technically, we are both correct. You are correct in the fact that INSTANTANEOUS Acceleration is at a maximum when the peak torque turns the crank, but the greatest acceleration over a time period is at the range where hp is greatest.

Make sense?


You are so close. I think we will get on the same page now that I can see where the communication broke down.

ac·cel·er·a·tion
NOUN:

1.
1. The act of accelerating.
2. The process of being accelerated.
2. Abbr. a Physics The rate of change of velocity with respect to time.

When I am taking about acceleration, I am using the literal definition. (see #2. above) With that usage, the maximum acceleration is at the torque peak. That is the point where, per RPM, the power is increasing at its maximum rate.

I think we agree on that. The step that you were missing on increasing the velocity of the car is that horsepower is not a constant function of the torque output. The horsepower formula simplifies to HP= tq x RPM/5252.

The RPM/5252 is the part that concerns us. That number is not a constant, it changes based on RPM (obviously). That is why there is more power available beyond the peak torque value's RPM point.

You were using the word 'accelerate' to mean 'changing the velocity of' the car, I was guilty myself of using that a time or two and I apologize for the confusion it generated.

Even though there is more power above the torque peak, the rate of change is less. The power is greater (car changes velocity over a shorter period of time), but the acceleration is less. The use of the word 'acceleration' is confusing here, so we will go with; The rate of power change is less.

I tried an example earlier, let's do a similar one and see if it makes more sense now. A vehicle makes 200ft*lbs of torque at 3500 RPM. That would be 133 horsepower. Call it 5 ft*lbs less @ 250 RPM on either side of it. So at 3250 RPM you get 131 hp and at 3750 you get 139 hp. That means you have gained 8 horses in that 500 RPM range. Now, lets look at what happens near the horsepower peak. Peak is at 6500 RPM. Torque is in the toilet at 140 ft*lbs, but the power is at 173. Since the torque curve is on the way down, lets say that it was 5 tq higher at 6250 (172 hp) and 5 tq lower than the 140 tq @ 500 RPM above that (probably more as when tq falls off, it really falls off.), but anyway, that gets to 173 hp (actually a touch more, my estimate was too generous with the tq since I claimed the power peak was at 6500.)

So from 3250-3750 RPM you gained 8 horsepower and from 6250-6750 you gained 1 horsepower. That is 500 RPM in each case. That is the acceleration, that rate of change over the 500 RPM. You had 8 times the acceleration around the torque peak vs the horsepower peak. The engine is reving 8 times faster.

The power generated is quite different, 131 horses vs. 173 horses. The vehicle will use that extra 42 horsepower (minus whatever is needed to offset increased drag and other parasitic losses) and will increase the vehicle's speed. So (and I hate using the word 'accelerate' here) the car will accelerate faster because of the increased power, but the engine is accelerating less quickly above the torque peak. Actually it is experiencing a negative acceleration, but who need to open that can of worms?

The engine accelerates most quickly at the torque peak, the car accelerates most quickly at the horsepower peak.

Since there is no constant ratio between torque and horsepower, any discussion regarding torque and acceleration is intended to be limited to the rotational acceleration of the engine. There is no context to compare it directly to power generated. Hard to explain....but since they are not related in a linear way, well, read the next paragraph and see if that helps.

Accelerating the vehicle depends solely on the power generated and that depends on another variable (RPM) in addition to the torque available at that point. So you cannot compare torque and vehicle acceleration directly. That is where I believe the confusion arose after you quoted the vette guy (or whomever it was originally)

Now, here is the last part. If the torque curve were perfectly flat (and this one is pretty close), the rate of acceleration would be the same, you would gain the same power over the same amount of time. The power curve would have the same slope all the way up. He was incorrect about the acceleration being the same @3000 RPM as @8000 RPM, but only because the tq numbers are not the same, if they were, then the statement would have been correct. The rate of change (aka acceleration) would have stayed constant.

You are so close. I think we will get on the same page now that I can see where the communication broke down.

ac·cel·er·a·tion
NOUN:

1.
1. The act of accelerating.
2. The process of being accelerated.
2. Abbr. a Physics The rate of change of velocity with respect to time.

When I am taking about acceleration, I am using the literal definition. (see #2. above) With that usage, the maximum acceleration is at the torque peak. That is the point where, per RPM, the power is increasing at its maximum rate.

I think we agree on that. The step that you were missing on increasing the velocity of the car is that horsepower is not a constant function of the torque output. The horsepower formula simplifies to HP= tq x RPM/5252.

The RPM/5252 is the part that concerns us. That number is not a constant, it changes based on RPM (obviously). That is why there is more power available beyond the peak torque value's RPM point.

You were using the word 'accelerate' to mean 'changing the velocity of' the car, I was guilty myself of using that a time or two and I apologize for the confusion it generated.

Even though there is more power above the torque peak, the rate of change is less. The power is greater (car changes velocity over a shorter period of time), but the acceleration is less. The use of the word 'acceleration' is confusing here, so we will go with; The rate of power change is less.

I tried an example earlier, let's do a similar one and see if it makes more sense now. A vehicle makes 200ft*lbs of torque at 3500 RPM. That would be 133 horsepower. Call it 5 ft*lbs less @ 250 RPM on either side of it. So at 3250 RPM you get 131 hp and at 3750 you get 139 hp. That means you have gained 8 horses in that 500 RPM range. Now, lets look at what happens near the horsepower peak. Peak is at 6500 RPM. Torque is in the toilet at 140 ft*lbs, but the power is at 173. Since the torque curve is on the way down, lets say that it was 5 tq higher at 6250 (172 hp) and 5 tq lower than the 140 tq @ 500 RPM above that (probably more as when tq falls off, it really falls off.), but anyway, that gets to 173 hp (actually a touch more, my estimate was too generous with the tq since I claimed the power peak was at 6500.)

So from 3250-3750 RPM you gained 8 horsepower and from 6250-6750 you gained 1 horsepower. That is 500 RPM in each case. That is the acceleration, that rate of change over the 500 RPM. You had 8 times the acceleration around the torque peak vs the horsepower peak. The engine is reving 8 times faster.

The power generated is quite different, 131 horses vs. 173 horses. The vehicle will use that extra 42 horsepower (minus whatever is needed to offset increased drag and other parasitic losses) and will increase the vehicle's speed. So (and I hate using the word 'accelerate' here) the car will accelerate faster because of the increased power, but the engine is accelerating less quickly above the torque peak. Actually it is experiencing a negative acceleration, but who need to open that can of worms?

The engine accelerates most quickly at the torque peak, the car accelerates most quickly at the horsepower peak.

Since there is no constant ratio between torque and horsepower, any discussion regarding torque and acceleration is intended to be limited to the rotational acceleration of the engine. There is no context to compare it directly to power generated. Hard to explain....but since they are not related in a linear way, well, read the next paragraph and see if that helps.

Accelerating the vehicle depends solely on the power generated and that depends on another variable (RPM) in addition to the torque available at that point. So you cannot compare torque and vehicle acceleration directly. That is where I believe the confusion arose after you quoted the vette guy (or whomever it was originally)

Now, here is the last part. If the torque curve were perfectly flat (and this one is pretty close), the rate of acceleration would be the same, you would gain the same power over the same amount of time. The power curve would have the same slope all the way up. He was incorrect about the acceleration being the same @3000 RPM as @8000 RPM, but only because the tq numbers are not the same, if they were, then the statement would have been correct. The rate of change (aka acceleration) would have stayed constant.
VERY nice post! Hopefully everyone that took basic physics will understand. ;)

VERY nice post! Hopefully everyone that took basic physics will understand. ;)


Thank you, however upon reflection, I did leave out just about the most important thing. It was so basic that I did not even consider writing it down, but it could be confusing.

The car will accelerate most quickly at the horsepower peak as that is the point where there is the most excess power above what is required to hold the current speed of the vehicle.

You are running the car in a gear that limits the top speed of the car by making it drag limited (like 5th) so, if the car accelerates and passes the point where it needs 172 horsepower to offset its drag/heat loss, it would be running (WOT) at 6250 RPM. Ignoring the extra wind drag at that speed, there is 1 extra horsepower available (excess power) to accelerate that car the next 500 RPM. Well, don't forget, you get more power during that 500 RPM window, a whopping 2 total hp to of excess power. You can imagine how long it takes the car to accelerate with those few horsepower.

Man...that took a long time. Now, think back to when you shifted into 5th and your RPM was at 3250. Engine is not guite lugging, but it is close and it takes 130 hp to maintain that speed. You floor the gas pedal and the RPM slowy climbs. You have the same 1 extra hp to accelerate the vehicle as you did at just below top speed, however during that same 500 RPM (3250-3750) you gain 8 horsepower. That means have more excess power available in that RPM range than at the first (6250-6750). The car will accelerate faster at the higher torque values (again, ignoring the extra drag from wind resistance).

The only reason a car will accelerate faster at the horsepower peak (unless running at close to top speed) is because gearing allows the engine to produce (and apply) the excess power to the wheels.

If you use the gearing (by shifting down to 3rd and getting to 6250 RPM ) to apply that 40 some-odd hp at the same speed as 3250 RPM in 5th gear, it is going to accelerate the vehicle a lot quicker than if you left it in the higher gear. It only gains 1 horsepower from the engine in the next 500 RPM instead of the 8 you would have in 5th, but you still have 40 excess horses straining at the bit accelerating the car. (ignoring the mechanical advantage change in the gearing)

I think we are ALMOST saying the same thing... but I think the use of the word acceleration is still screwing us up. :)

Technically, based on F=m*a, the maximum acceleration is @ the peak TQ, the force. When the crank turns @ peak torque, you are getting your maximum INDIVIDUAL acceleration.

Effectively, however, which is what we are actually interested in with regard to racing, maximum acceleration over the course of any significant time period is at @ maximum
hp.

Hopefully this will help...

Let's say you're at maximum tq of 400... the acceleration is maximum PER CRANK REVOLUTION. I will show this with 4 underscores...

____


Now, imagine that you are at your maximum hp, which happens to be only 3/4 ths of the maximum torque. (shown by 3 underscores)

___



Now, lets say that your maximum torque is @ 4k rpm, so scaled down, every minute, your acceleration will look like this (scaled down to 4 instead of 4000)

____
.......____
..............____
.....................____

So, total acceleration over that minute is 4 (4000) times your maximum individual acceleration, so your POWER, which is Work/Force with regard to time, would be 16 (4 rpm x 4 underscores of acceleration per minute). BTW, this is not in hp because it's much simpler if you don't use those arbitrary units of power. The actual hp at this point would be
304hp based on the formula for hp.

Now, let's look at the point of greatest power, which we will say is at 8000rpm, but only 3/4's of maximum torque (300). So, with 300tq and 8000rpm, the hp here is 457hp... or, in our simple form of power, 24 (8 rpm x 3 underscores of acceleration per minute). Now, for the representation.

___
.....___
..........___
...............___
....................___
.........................___
..............................___
...................................___



Now, lets see them next to each other...



[B]Maximum TQ : 400 tq (4 underscores of acceleration) and 4000rpm (4 sets) = 304hp (16)
____
.......____
..............____
.....................____



Maximum HP :300 tq (3 underscores of acceleration) and 8000rpm (8 sets) = 457hp (24)

___
.....___
..........___
...............___
....................___
.........................___
..............................___
...................................___

As you can see, the individual acceleration PER CRANK ROTATION is greater at peak TQ, but the acceleration over a given time period, in this case, 1 minute, is significantly higher at maximum POWER.




Hopefully this clears up the confusion we were having :) I think the fact that there were 2 different 'kinds' of acceleration... actually just over different time periods... is what was throwing us off.


There are other things like when you should shift and what happens when hp is dropping off that I would like to try and clear up as well, but rather than try and put too much into this post, I'll just tackle that later.

As I was reading this I had a flashback to my 3 hour Physics Lectures. Man I dont miss those days!!

I am amazed everyday at the amount of extremely intelligent people on this website. This place is a gold mine of information!!!

We should increase the TORQUE on those cars ...

not the true defenition...but this is how i explain tq
tq is the energy of ONE revolution of a engine...whereas HP is that number times how many revolutions....

so many people miss the point it's crazy. hp doesn't even really exist. It's just a figure derived so a car salesman doesn't have to write a science equation on a sales tag. Tq never changes in a motor unless you modify it. Rather the eff. at which tq is applied goes up and so you get a tq curve and have a higher tq # at different rpms then others.

Tq is the actual measurement of power in ALL engines. Hp is just an acceptable term so salesmen don't have to give a crash course in physics to your average joe looking to buy a car.

Horsepower, horsepower, horsepower. That's what it's all about.

Torque does not equal acceleration. As someone pointed out already, if I put a one foot long wrench on the lug nut of my car and apply all my weight to it (Let's say 200 lbs.) and tighten that lug nut as tight as I can (without jumping) I'm applying 200 lbs/ft of torque.

Even if the lug nut doesn't spin anymore, and the car doesn't move (read the wheel doesn't spin either) then I'm still applying torque. Torque doesn't need motion to exist. HP does.

I don't care if you apply 2,000 lbs/ft of torque to any axis (drivetrain, crankshaft, axle, or whatever), if the vehicle doesn't move no HP is being produced. If no HP is being produced, the car doesn't move.

You can't have one without the other.

No HP = No motion and vise versa.

applying tq and making it are two different things

TQ gets it moving, HP keeps it moving.

horsepower is how fast you CAN go, torque is how long it takes to get there. You cant have one without the other

at least thats always been how ive seen it

horsepower is simply a measurement of torque. Torque gets it moving, torque and momentum keeps it moving.

horsepower is simply a measurement of torque. Torque gets it moving, torque and momentum keeps it moving.

exactly....HP = TQ / Time you have to realize they are essentially the same thing

heres a good article
Comparing Two Cars

I think at this point, it is clear that the car's acceleration ability is related to its engine's power output. Now, let's compare two different cars with two very different engines.

Both vehicles will have the same curb weight, and peak horsepower figures. They will also have the same transmission, tire radius, and so on. In fact, the only difference between the two cars will be the engines. One car will be equipped with a 500hp turbocharged 4 cylinder engine, and the other will have a 500hp big-block V8. The 4 cylinder will be named Ricer, and the V8 will be named Redneck. The 4 cylinder is able to rev to 9000rpm and produce a fair bit of torque, while the V8 can rev to only 6000rpm, but produce a ton of torque. To keep the math very simple, the Redneck's engine idles at 600rpm, and the Ricer's idles at 900rpm.

Below are plots of the two fictitious engine's torque and horsepower curves.
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled1.jpg
Figure 1: Torque versus RPM for Redneck and Ricer. These are unrealistic curves which have been exaggerated to help illustrate certain concepts.
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled2.jpg
Figure 2: Horsepower versus RPM for Redneck and Ricer. This is calculated from the torque at each RPM.

Both engines produce a peak of 500hp, just like I promised. The V8 produces 500hp at 5000rpm, and 573tq at 4250rpm, while the I4 produces 500hp at 8000rpm, and 337tq at 7500rpm.
Ricer Redneck Difference
Rev Range 900 - 9000RPM 600 - 6000RPM 50% more for Ricer
Peak Torque 337tq 573tq 70% more for Redneck
Peak Power 500hp 500hp Equal

Because the V8 was revving lower, it needed to produce more torque than the I4 to reach the same peak power figure. Conversely, the I4 needed to rev higher than the V8 to produce the same power, because it offers up less torque.
The Power Band

A very important aspect of an engine's output is its power band. The power band is the rev range where the engine is producing an arbitrary percentage of its peak power figure. I will use 80%, which is 400hp or more on our two 500hp engines.
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled3.jpg
Figure 3: Power band comparison of both motors. Note that the Redneck's average power production (area under the curve) is higher, and that the peak power is the same, at 500hp.

The x-axis may seem unusual. Because the Redneck's engine revs from 600rpm to 6000rpm, while the Ricer's engine revs from 900rpm to 9000rpm, the power production cannot be compared directly with revs. The Ricer has a 50% greater rev range than the Redneck, so the Redneck's graph has to (or "gets to") be stretched by 50%. Showing the x-axis as a fraction of each engine's rev range helps to equal the comparison.

If this seems confusing, there is a separate page on comparing power curves which explains why the rev ranges can't be compared directly.

We will see later on that Figure 3 is a more accurate comparison of the two engines ability to accelerate a car than Figure 2.

Notice that while both engines have the same peak power figures, the Redneck's engine has a much wider 80% power band. This situation is a considerable advantage for the Redneck. Between the two cars, the one with the made-up V8 is going to be faster than the one with the made-up I4, because the V8 has a higher average power level throughout it's rev range.

An exotic sportscar, such as a Lamborghini Murcielago, will have such a wide power band that it can accelerate very hard from almost any RPM. This means that it can do things like go from 0-60mph in one gear. This is why exotics have such impressive performance.
Force on the Road

Let's now look at how much force the Redneck and Ricer are putting to the road, which as we talked about earlier, is the force which accelerates the car. For simplicity, both drivers will race by rolling from 20mph, flooring it, and then shifting at their redlines in each gear. Top speed will be considered redline in top gear, because we are ignoring aerodynamic drag.

We'll start off by giving both of them a good old TH350 3-speed automatic transmission, and a 3.73:1 final drive (axle) ratio.
Drivetrain Layout
TH350 and 3.73 Axle Gears
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled4.jpg
Figure 4: Rear wheel force versus vehicle speed for Redneck and Ricer when using a TH350 transmission and 3.73 axle ratio. The steep vertical drops are the gear changes at redline. Gear changes take place instantaneously for simplification.

Notice that the Redneck has a considerable advantage over the Ricer in first gear, but then not so much in second or third gear. This is because when he shifts into 2nd gear, the transmission doesn't bring him back to idle, but to approximately 3600rpm instead. The Ricer's engine also stays in reasonably high revs after the first gear change, and we saw in Figure 2 that he has plenty of power at high revs. Also note that the Redneck had to shift into second before the Ricer, so his ability to accelerate between 60-65 and 100-115mph is about the same as the Ricer's.

Now, let's move into modern day by giving them both a Tremec T56 6-Speed close-ratio manual transmission.
Drivetrain Layout
Tremec T56 6-Speed and 3.73 Axle Gears
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled5.jpg
Figure 5: Rear wheel force versus vehicle speed for Redneck and Ricer when using a Tremec T56 transmission and 3.73 axle ratio. Note that the close ratio transmission has reduced the drops in power at each gear change for both motors, especially for the Redneck's.

At certain speeds, the Ricer has caught up slightly. The close-ratio 6-speed transmission helps keep his engine revving near his power peak, and that has helped narrow the gap. The small dips on the Ricer's graph show the effects of having a narrow power band.

The Ricer's acceleration in first gear is still very poor, but the Ricer has a trick up his sleeve. He is going to install a set of 5.67:1 gears in his axle without the Redneck knowing.
Drivetrain Layout
Tremec T56 6-Speed
3.73 Axle Gears for Redneck
5.67 Axle Gears for Ricer
http://i34.photobucket.com/albums/d147/hunterkiller89/untitled6.jpg
Figure 6: Rear wheel force versus vehicle speed when using a Tremec T56 transmission and 3.73 axle ratio for the Redneck, and 5.67 for the Ricer. Note that both cars shift gears at about the same vehicle speeds as each other now.

The Ricer has pretty much completely caught up now, especially at speeds above 40mph. With those gears he put in, he has traded his higher revs for higher torque to the wheels. Now, for certain vehicle speeds, he can accelerate alongside the Redneck.

The Redneck would also see benefit from putting in different axle gears. However, this "arms race" cannot go on for long, because as the wheel torque is increased, speed is traded away. It would be very embarrassing for the drivers if they crossed the finish line sitting at redline in 6th gear, not accelerating. The Ricer can use a lot more gear because of his extra revs. Conversely, the Redneck doesn't need them because he has so much flywheel torque that he doesn't need to multiply it as much. There is not a significant benefit to either driver in this regard.

If we fitted both cars with a Continuously Variable Transmission (CVT) that had an infinite ratio spread, which can hold both engines at their horsepower peaks, the acceleration of both cars would be identical at any vehicle speed.
Low-Speed Acceleration

Even after changing the rear axle gears, the Ricer's car still could not match the Redneck's acceleration from a slow roll up to about 35-40mph. This shows that the benefits of a having a very wide power band are most significant in first gear, and is therefore an important part of tuning an engine for drag racing, where the cars start from rest.

here's a simple answer.....anything under 60mph thats where the trq does the job...anything over 60mph is where the hp does the job...

look at the s2000's....horrible cars off the line,but highway they are pretty solid cars since they got 250hp but only 150ish trq

here's a simple answer.....anything under 60mph thats where the trq does the job...anything over 60mph is where the hp does the job...

look at the s2000's....horrible cars off the line,but highway they are pretty solid cars since they got 250hp but only 150ish trq

...thats really not true at all though...if your going to say where the numbers matter...than you would be more correct in saying TQ does the work from 1kRPM through 3-4kRPMs, whereas HP does the work from 3-4 through redline....and once you get to a higher rev point, you'll stay there because when you shift, your revs wont go back down to 1kRPM

even this isnt really accurate though...but its a simple way to look at it