horsepower.......

[conmemay852005]

Hi everyone, can someone tell me what is hpower vs whp and how to calculate them? or r they the same?
thanx

[Dave_B]

Hi everyone, can someone tell me what is hpower vs whp and how to calculate them? or r they the same?
thanx

Most HP ratings are at the Flywheel. When a car manufacturer puts out HP numbers, it's at the FW.

When your talking WHP, that car has been on a dyno and the HP number is measured from the wheels, and not the FW.

Due to drivetrain loss, you loose close to 15% HP numbers.

So FW HP will be approx. 15% higher than WHP.

Then there are different dyno's that read different... but that's a whole nother story.

[Jan Niemi]

torque is measured, after which hp, or whp is calculated.

HP is calculated by using an engine dyno
WHP is calculated by using a chassis dyno

torque is the work performed, which can be measured.

The formula for calculating hp from torque is

hp = (torque x rotational speed) / 5252

for example, let's say your car makes 190 ft. lbs. torque at 7500 rpm.

So 190x7500 = 1425000

Now divide that by 5252

1425000/5252=271.33 hp at 7500 rpm.


Torque and HP are always identical at 5252 rpm. Just look at any dyno graph for proof.

Hope this helps..

[Erik B]

Jan your sucha nerd!!!!!!!! hahaha