A usefull tool..
"Converting wheel bhp to flywheel bhp and vice versa
To reflect the fact that % losses are high for low powered cars and vice versa I use the following equations which have been found to correlate well with real world transmission losses.
FWD cars - add 10 bhp to the wheel figure and divide the result by 0.9
RWD cars - add 10 bhp to the wheel figure and divide the result by 0.88
4WD cars - add 10bhp to the wheel figure and divide the result by 0.84
To estimate the expected wheel bhp from a known flywheel bhp just reverse the equations
FWD - multiply flywheel power by 0.9 and then deduct a further 10 bhp
RWD - multiply flywheel power by 0.88 and then deduct a further 10 bhp
4WD - multiply flywheel power by 0.84 and then deduct a further 10 bhp
Remember, these percentages are not "gospel" - they are good realistic averages."
The rest of article is at http://www.pumaracing.co.uk/power3.htm
Handy tool MD . I will keep the maths in mind at our next dyno day at Beninca's