What is meant by brake horse power in cars?
Brake horsepower (bhp) is the measure of an engine's horsepower
without the loss in power caused by the gearbox, generator,
differential, water pump and other auxiliaries. Thus the prefix
"brake" refers to where the power is measured: at the engine's
output shaft, as on an engine dynamometer. The actual horsepower
delivered to the driving wheels is less. An engine would have to be
retested to obtain a rating in another system. The term "brake"
refers to the use of a band brake to measure torque during the test
(which is multiplied by the engine speed in revs/sec and the
circumference of the band to give the power).