Multiply by 0.82 for rwhp... found it on HPF

 

maybe

 

X2.81

 

lets say a car makes 500 crank hp with x.81 its really making 405 at the wheels..

 

I was being a smart azz because your initial question was vague as to what number you were x.82 to get rwhp....

Now your question makes more sense. You are trying to estimate crank HP from WHP or vice versa. I think the factor on a modern RWD car is about 15%. So if you made 850whp it would be approximately 1000hp.

I think the .82 would be about 18% but it is all pretty much estimates anyway as different platforms have different drivetrain loss factors. Obviously older cars, automatics and AWD cars have higher drive train loss and I have heard they are more like 20% loss.

By 15% your 700whp car is about 805hp

 

This was my baseline and I got a revup (298hp) so do the math and see how it works

Mine comes out to .79

 

with .82 you should be at 244 whp which is about right as what i hear on the Gs..

 

15% of 745whp = 856 hp
908(hp) x .82 puts me at 744whp

 

The OEM baseline was done with no accessories so it caused our whp numbers to be on the low side as to what was expected for a 287whp car. My DE was never on the Dyno until I had cat back, CAI and spacer and it only made 230whp so I need 25% to make OEM numbers and that was with minor mods already. So my 600whp would equal 750hp by that math. Like I said no matter what math you try it is an estimate at best.