Can someone tell me the how to work out hp at the wheels
to hp at the fly wheel ie i have 270hp at the wheels of my
Rex what would it be at the fly wheel

It's all guesstimates, but add a third

or 270hp atw = (roughly) 270kw flywheel

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A nation of sheep will beget a government of wolves.

wrong

losses are static, its not a % of loss.. 270 at the wheels will IMHO be about 320-330 at the fly wheel given the losses of a rex box, maybe even less..

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Jesus Built my car, Its a love affair, Mainly Jesus and my hotrod

Wrong again

There are static & "percentage" factors involved,
but it would be a complex algorithm that could take it all into account,
especially as it is different for each gearbox/diff/drivetrain configuration.

Let's agree to disagree?

__________________
A nation of sheep will beget a government of wolves.

Generally The total hp of the car (what the engine produces) - approx 27% (drivetrain/gear losses etc) gives u the horsepower at the wheel.

So in your case just work the opposite way. You know hp at the wheels so just ad 27% and thats an approximate.

As AWDmoke sed there are many factors involved. So the normal thing wud be to us a factor of 27%

i'm aware it's a straight 70hp ish difference and is replicated on most dynos.

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E92 BMW M3 - silverstone silver
Ducati 1198S - red

www.lumensphotography.com

PERCENTAGE LOSSES ARE FUCKING WRONG

i don't know how many times i have to repeat that, drive train losses are STATIC, they DO NOT change, with the SLIGHT exception of a couple of hp either way due to stuff like better oils in the drive line..

if you make 200hp at the fly wheel, and see 170 at the wheels, you have a 30 hp loss

if you suddenly make 400hp at the flywheel, you will see 370 hp at the wheels, the only thing that will change drive train losses, are a severe change in driveline, if you change nothing but the motor and its power output, the loss value WILL NOT ALTER

there is no % formular, its a straight up and down fact, go tell and engineer you think its a % and he'll rightfully laugh at you..

__________________
Jesus Built my car, Its a love affair, Mainly Jesus and my hotrod

you mean 70kW?

yep engine power --> wheels

__________________
E92 BMW M3 - silverstone silver
Ducati 1198S - red

www.lumensphotography.com

This topic seems as if a can of worms has been open

THANKS FOR YOUR INFO GUYS