Bone1

BTW, What is Horsepower?

T * T

QikEnuF

The amount of power one horse puts out :1

0b00st0

Now you've proven that you don't know what you are talking about and are a complete fool. Shifting at 7000rpms does not yield maximum acceleration.

You should've run that motor out to 7500 to see were horsepower really drops off. Stopping at 7000 was foolish. The most area under the curve would've been at around 7200-7300 shift point.

It's area under the horsepower curve, NOT the torque curve. Even though the motor makes less torque at higher rpms, it makes more power which takes advantage of gearing.



Power = torque * acceleration

Again, torque is not a unit of energy. Torque without revolution is worthless. Horsepower is a unit of energy. Even though you may have less torque at higher rpms, the are under the horsepower curve is greater, thus higher acceleration.

Bone1

Your calling me an idiot with this simple statement........

Understand what tq curves and HP curves are. FIRST know what HP is in relation to TQ. I'll give you a simple number

5252.5252525252

Why should have I tried taking my motor out to 7500 rpms when it was falling on it's face? I was shifting at 6500-6600 for best ETs. The power loss was known, part of a problem with Crome. But even without that issue HP was falling off and TQ went south to Mexico.

Please just anwser the ONE major question.

What is HORSEPOWER?

Now, I've discussed gearing with Gale Banks (who started my gearing madness in 1983) and have talked on the phone with John Lingenfelter about the C&D 40th Vette, also with a SCCA National Championship last year and other little wins. From drag racing Honda side of things, best is a low 11 sec pass D16 before getting booted for no cage. Maybe I have a CRX 4th gear into a 5g WHITE HB going 10's, but no vids lately.

I'll stop now, 6 pack almost gone.........

.......your thoughts about reving out the motor beyond it's limits/power curve is a simple reason little D's end up walking DOHC VTEC B's due to drivers trying for 9 MILLION RPMS in a torqueless motor.

0b00st0

Yes they are one one number away from each other, BUT that makes all the difference when integrating the curve to find the most area over the rpm drop.

HINT: When you integrate a curve, line, or any function, you find the area underneath.

Go look up what integrating is. Here, crude but nonetheless helpful: http://en.wikipedia.org/wiki/Integral



Going off of what you are saying, if a motor makes a constant 100ftlbs of torque between 0 and 8000rpms, you could just shift anywhere, cause the torque is the same and the area under the torque curve is the same and the car will be the fastest no matter what.

See where it matters now? Obviously horsepower will rise and the higher up, the more area under the curve. It's because horsepower shows energy production, torque does not. 100ftlbs at 4000rpms is less energy than 100ftlbs of torque at 8000rpms. The latter allows lower gearing and makes 200ftlbs of torque at the same speed as the subsequent output.


It's like only using current to calculate energy usage. You can't do that without electromotive force (voltage). This is why units are what they are in world. Torque is not a unit of energy. Horsepower is however.

miss-piggy

Madmax is right. I was wrong. I wasn't thinking things through.

JonDouglas

But torque is the only thing that matters. As long as you have 5 bajillion ft.-lbs of torque at 0.0002 RPM, that is all that matters.

:P

Bone1

If Horsepower is torque over a period of time then explain this

"It's because horsepower shows energy production, torque does not"

A) Step away from the train driver handbook
B) Do some real world testing or atleast research it.

Torque moves mountains, HP wins bench races.

0b00st0

It's this statement that shows how truly ignorant you really are.



You just did. A constant amount of torque does not indicate how much energy is being produced. You need to know rpms to calculate power.

Power is torque over time.

t_cel_t

ok so that dyno sheet is your car right?

go get a stopwatch and get in 3nd gear and floor it at 4500rpm and hit the stopwatch untill you get to 5500

then do that same thing from 5500 to 6500

i guarantee that it is almost the EXACT same time.
yes at higher rpms you are doing more 'work' but the engine is not pushing against the wheels any more then it did at lower rpms, its just pushing at a higher speed.