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Former '05er
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Discussion Starter · #1 ·
There seems to be an interest in torque as a discriminator of engine performance. Torque is just a number having little to do with anything about how an engine performs.

I can hear it now. HERETIC! BURN HIM AT THE STAKE!

BUT, the truth about torque is it means nothing to the car. Horsepower is everything, because it is the ability to do work (in the physics definition of work) that really separates the strong from the weak. Your gearbox and final drive ratio to alter torque to suit the application.

Example:

2004 F1 engine makes over 1000 hp at ~19,000 rpm
1991 F1 engine makes over 1000 hp at 9500 rpm

Same power output, different rpm. The 1991 engine has twice the torque of the 2004 engine, yet the cars are equally as fast. Why? The available torque at the drive wheel is identical, because the gearing is completely different. The engines just make power differently.

Another example, many diesels make ridiculous amounts of torque. some over 1000 ft-lbs. Why don't they leave everything for dead when they launch? Redline at 2500 rpm doesn't make a lot of horsepower. And no, trucks don't use diesels because they make lots of torque, it's because they are significantly more thermally efficient than gasoline engines.

If big torque numbers were important to acceleration, Top Fuel would be a contest of diesels. Obviously it isn't. Nitromethane and methanol make LOTS of horsepower in engines spinning very high rpm (for their size) power the elite classes in drag racing.

Torque is only useful when related to rpm so we can figure out how much POWER we have.
 

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Ironhead
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would you say that the reason i can launch off a line faster than a celica is because it has more horsepower? or because torque generates power, whereas horsepower maintains it, and i have a significant torque advantage? or because my torque is generated at a lower RPM than the celicas? or because my horsepower peaks at a lower rpm than the celica? or is it a combination? if we took the hp rating of the tc, left everything else alone, and dropped torque on the engine somehow to 97lbs, would i still 0-60 in the same time? would i be able to stomp an integra still?

edit : dont think i am being a torque-nazi or anything. i just want to make sure i have a clear picture of what you are saying. trying to get the context, i suppose. thanks.
 

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Former '05er
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Discussion Starter · #4 ·
You have more torque available at the wheel than the other cars. This has nothing to do with how much torque the engine is making, because we are optimizing the torque at the wheel by using a variable ratio gearbox.

First gear has a very high multiplication factor to make it easy to launch the car. Notice you can't stay in first for long without running out of rpm. It is precisely because the multiplication factor for first is very high.

Consider what would happen if you tried the same feat in second. You would certainly lose. Not because the engine fails to make good torque, but because the torque at the wheel is not as good because the multiplication factor is lower.

Also consider your launch rpm. Do you launch at 1000 rpm when to want to take off fast? Of course not. You launch at 4000 rpm and slip the clutch mightily because you want the POWER available at 4000 rpm, and you modulate the clutch to keep the torque at the wheel from overwhelming the tire's grip with the pavement.

Does that make more sense?
 

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omg this guy is smoking crack......
think about this ding dong.....
you have a dangerously high revving motor with low displacment and a lower revving equally powerful high displacement motor which do you think will last longer.
further-more torque and horsepower go hand/hand in making a good motor. the TORQUE is the low end power that pulls you from the line and the hp is the over all top end power.

when people revv the engine before a launch its to prevent bogg or lag...and take off within the engines maximum torque band.......

go back to ITT Tech - haha
 

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Discussion Starter · #7 ·
Originally posted by functionoverform@Dec 20 2004, 12:06 AM
omg this guy is smoking crack......
think about this ding dong.....
you have a dangerously high revving motor with low displacment and a lower revving equally powerful high displacement motor which do you think will last longer.
further-more torque and horsepower go hand/hand in making a good motor. the TORQUE is the low end power that pulls you from the line and the hp is the over all top end power.

when people revv the engine before a launch its to prevent bogg or lag...and take off within the engines maximum torque band.......

go back to ITT Tech - haha
Crack?

ITT?

Dangerously high revving? I bet you don't even know how to calculate redline or what the acceptable limits and their relative service lives are.

Surely your ignorance is only exceeded by your arrogance. Before you continue to berate my skills, maybe you should do a Google search for hp vs. torque. Or better yet, just click here to educate yourself. Be sure to read all the way to the bottom where Texan clearly illustrates the utter stupidity of your claims.

Oh, yeah, I've built engines for racing and street applications for about 25 years now. I don't need any input from someone who clearly has no grasp of simple physics.
 

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Does that mean lo bux did some break dancing?
 

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Oh great. Its a HP vs TQ fight. Aight time for some schooling.
1. The torque produced by the engine is what is moving your car, and horsepower how fast its being produced.
2. Think of horsepower as Power, which for this discussion is energy x time. 1 horsepower is equal to 550 lb/ft of torque per second, or simply "torque over time".
3. Horsepower is not torque; therefore they cannot be compared. Ever.
4. Which is more important? Both, you must have a good combination of both.
5 If anyone says torque doesnt matter and HP is king look at yourself. because HP is the product of torque.
 

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Former '05er
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Discussion Starter · #12 ·
Comparing engines or cars by torque numbers is pointless. The only useful comparison is horsepower. Saying a car has a weight to torque ratio of anything is useless because it fails to take gearing into account.

However, I build engines for torque in the most useful powerband. If I were to compare tC to tC, then torque would be useful because all the other variables are the same. You can't compare tC to anything else (Prelude, Integra, RSX, etc.) by torque, it is meaningless. But if I say MY tC has 10% more torque than yours, I clearly have more power and I will (assuming all else is equal) accelerate faster than you will.

Make sense?
 

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^^^ this is all correct. Good job. Is comparison by torque #'s all you wanted to disprove? or was it that torque wasnt needed?
 

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Ok, how about a simplified example for slow people (me)?

Let's say we have 2 cars with same weight, same gear / final drive ratios and tire size. One is powered by 2AZ (160hp/165tq), and another one by RSX/Si engine (160hp/130tq?). Since all we care about is HP - does it mean that the cars will be identical in terms of 0-60 and 1/4?

Again, I'm a computer nerd - I know nothing about engines, so please keep it in mind
 

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Ironhead
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Originally posted by functionoverform@Dec 20 2004, 12:06 AM
omg this guy is smoking crack......
think about this ding dong.....
you have a dangerously high revving motor with low displacment and a lower revving equally powerful high displacement motor which do you think will last longer.
further-more torque and horsepower go hand/hand in making a good motor. the TORQUE is the low end power that pulls you from the line and the hp is the over all top end power.

when people revv the engine before a launch its to prevent bogg or lag...and take off within the engines maximum torque band.......

go back to ITT Tech - haha
see, its sh!t like this that pisses me off. you got served doesnt begin to say it. you got served before you even hit one keystroke. your ignorance is astounding. if you dont know who and/or what you are talking about, stay out of it. no one needs your arrogance, or your ignorance. not in my forums.


lance, i am totally on the same page as you now. for a second it was coming across like you wanted me to believe that torque itself is useless. now i see the details in your thinking that were not evident in the initial post, and i am on board with you now for sure. thanks for the clarification, i neglected to think about torque properly in my last racing post.

for the record, i would pay to see lance breakdance.
 

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Former '05er
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Discussion Starter · #18 ·
Sorry guys, I'm a disabled Vet. For real. My lower back doesn't take any abuse anymore.
 

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Originally posted by lo bux racer@Dec 18 2004, 01:31 PM
There seems to be an interest in torque as a discriminator of engine performance. Torque is just a number having little to do with anything about how an engine performs.

I can hear it now. HERETIC! BURN HIM AT THE STAKE!

BUT, the truth about torque is it means nothing to the car. Horsepower is everything, because it is the ability to do work (in the physics definition of work) that really separates the strong from the weak. Your gearbox and final drive ratio to alter torque to suit the application.

Example:

2004 F1 engine makes over 1000 hp at ~19,000 rpm
1991 F1 engine makes over 1000 hp at 9500 rpm

Same power output, different rpm. The 1991 engine has twice the torque of the 2004 engine, yet the cars are equally as fast. Why? The available torque at the drive wheel is identical, because the gearing is completely different. The engines just make power differently.

Another example, many diesels make ridiculous amounts of torque. some over 1000 ft-lbs. Why don't they leave everything for dead when they launch? Redline at 2500 rpm doesn't make a lot of horsepower. And no, trucks don't use diesels because they make lots of torque, it's because they are significantly more thermally efficient than gasoline engines.

If big torque numbers were important to acceleration, Top Fuel would be a contest of diesels. Obviously it isn't. Nitromethane and methanol make LOTS of horsepower in engines spinning very high rpm (for their size) power the elite classes in drag racing.

Torque is only useful when related to rpm so we can figure out how much POWER we have.
I'm sorry but you're a moron. You obviously know NOTHING about an engine if you think torque doesn't matter.

torque
n.
The moment of a force; the measure of a force's tendency to produce torsion and rotation about an axis, equal to the vector product of the radius vector from the axis of rotation to the point of application of the force and the force vector.


Let's go Hypothetical.. Let's Take Two Scion TC.

One Engine Has :

160hp @ 5700rpm
163lbstq @ 4000rpm

The Other Has

150hp @ 5700Rpm
200lbstq at 4000rpm

If you actually think the Scion with more horsepower and less torque would win... Then you need to do some reading about engines.

The only reason my GTP can run those times is because of my Low end Torque.
 

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*cough*
 
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