What is more power awhp or bhp,flywheel>?

[GTO-SIMON]

What is the grater power ?eg 450 bhp or 450 awhp?

[futurevr4man]

450 awhp...

is this a serious question?

[sergechronos]

BHP is a measure of how much horsepower the motor itself has.
AWHP is a measure of how much of that horsepower is actually making it to the ground after drivetrain losses.

Factory horsepower ratings of 320hp are measured at the flywheel, actual power to the ground is significantly less. General rule of thumb is to take the BHP and subtract about 10-15% to get a rough estimate of wheel horsepower.

[GTOJOE]

I think this is in reference to the fact UK dynos do not measure WHP [well they do but they don't give that number out] they measure it and calculate the power of the engine [at flywheel] taking into account driveline loss etc. It doesn't make much sense but the reasoning is to give a better indication of how much power increase there is over the stock numbers etc. However none of the numbers seem to match up with USA dyno numbers etc when taking power at the wheels then taking away driveline loss you will get nothing like the UK dyno numbers. It's an old subject and one that will never get a resolution. All UK dyno operators use this method I believe so don't try to compare your numbers to USA numbers. Compare them to cars over there.

[anyonebutme]

I still can't find anybody who races dyno's.........trap speed is the real HP calculator.

[TwIzTeD_3kGt]

Here's this again. Hopefully it doesn't turn into what the last one turned into.


Brake horsepower (bhp) is the measure of an engine's horsepower before the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired rotational speed. During testing, the output torque and rotational speed were measured to determine the brake horsepower. Horsepower was originally measured and calculated by use of the "indicator" (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft.

More recently, an engine dynamometer is used instead of a De Prony brake. Although the output delivered to the driving wheels is less than that obtainable at the engine's crankshaft, a chassis dynamometer gives an indication of an engine's "real world" horsepower after losses in the drive train and gearbox. This gives a reasonably accurate indication of how a wheeled vehicle engine will perform once on the road. (AKA WHP)

[wingnut]

lol :D in on one...

[Tigchamp]

The trouble is Simon that a Dyno operator can set the dyno up to read anything you like, as Ben @ Eurospec demonstrated at the last GTOOC Rolling Road day.
If you want you could probably get a bog standard TT to show 500 AWHP.
As said before the best guide is 1/4 mile times, but even then you have tracks that are uphill like Santa-pod in the UK or others that are down hill. Some have good grip others don't, then you have prevailing wind direction:Doh:
Jeff:coo3l: