BHP -Wheel horsepower v Flywheel horsepower

[Paul@1320]

So what run down losses did you have Roland??

So you are saying that you could put your turbo engine on an engine dyno and make 391bhp put it in car and put it on our dyno and it makes 344whp but put it on a Maha it makes 290whp and thats okay

Personally I like to have the lowest sapping horsepower possible from the flywheel. And as you've quite rightly said in the past that huge run down losses might be a wheel bearing tracking etc etc

[roland2003]

The losses of the actual car are no more or less on a Dynojet than a Maha.
The losses show more on the Maha partly because its a two roller system . It uses complex software programs to measure the losses . Loses are higher if you use a higher gear as we had to due to the absurdly high power I'll put the losses of using 6th gear up on the GTT300T thread.
Are you measuring losses on every run you do?
Do you just want a RR type that shows the higher WHP figure to impress people ? Or would you rather have a RR that measures everything to provide a meaningful Flywheel power figure.
Audi, bently, Caterham, Dawoo............Yugo . The A to Z of car manufactures,everyone quotes Flywheel Power. -No other method means anything.
Are you deliberatly pretending not to understand?
I think you know very well Im right here.

[BRMCooper]

easy Roland! we dont want a handbag fight over this!

all im saying is at the end of the day the wheels are whats touching the ground so thats the power the cars putting out, you could have 1000bhp if you have 999bhp tranny los then its only putting 1bhp on the black stuff ok the engine is still making 1000bhp but the CAR only has 1whp

we could go in to "what gear" "wheel size" ect ect when it all done and pasted and your sitting on the track its whp that'll get you going

like a good man once said "a rr is only a mesurement device to see IF what you have done works"

[roland2003]

BRM this is the conclusion many people come to when they havn't thought it through and read up on it. Go back and read the whole thread.
Alternativley if you dont believe me read Dave Walkers tuning books or Performance tuner mag .... he's probably the UKs No1 technical tuning Guru. He will tell you exactly the same as me.

[Paul@1320]

Yup ours is four rollers and uses the latest TAT complex software program to measure the losses on every run we do, all figures are corrected for air pressure and temp to DIN standard.

We also check the calibration of the dyno monthly.

I know Lee's probably itching to get hold off it but it would be intresting to put it on another dyno what can hold the power, a hub dyno defintley would hold it

[BRMCooper]

Quote: Originally Posted by roland2003 (original)

BRM this is the conclusion many people come to when they havn't thought it through and read up on it. Go back and read the whole thread.
Alternativley if you dont believe me read Dave Walkers tuning books or Performance tuner mag .... he's probably the UKs No1 technical tuning Guru. He will tell you exactly the same as me.

Right'o'

[Revolution Mini Works]

wow... just take it to the track and shut everyone up

course we did that and people still don't believe the times as we beat race cars with our street cars