Car guys

Stumps

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Jun 18, 2001
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no, they aren't, BHP is measured at the flywheel, HP is at the back wheels, depending on the type of vehicle this figure can vary between 15% and 30%.
 

Chrono

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Jan 2, 2001
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I thought HP = BHP = Flywheel = the same?

but HP @ the wheels = different
 

blodhi74

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Mar 28, 2003
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Originally posted by: Stumps
no, they aren't, BHP is measured at the flywheel, HP is at the back wheels, depending on the type of vehicle this figure can vary between 15% and 30%.


If one was measure both, which number will be greater on a vehicle?
 

Stumps

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Jun 18, 2001
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the terms are often mixed up, but they are different, BHP is general used by manufacturers to make their car sound powerful, while HP is used by performance guys because it gives a better indication of how much power a car actually puts to the ground
 

Stumps

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Jun 18, 2001
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Originally posted by: blodhi74
Originally posted by: Stumps
no, they aren't, BHP is measured at the flywheel, HP is at the back wheels, depending on the type of vehicle this figure can vary between 15% and 30%.


If one was measure both, which number will be greater on a vehicle?

BHP gives a higher figure because it is what the engine actually produces, but tranmissions and differentials reduce this figure signifigantly when the power reachs the back wheels, generally manuals give less drivetrain loss than auto's, same goes for RWD vs FWD/AWD/4WD
 

shabby

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Oct 9, 1999
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hp = a formula, torque * rpm / 5252
bhp = is a machine that uses a 'brake' to measure the true power of the engine at the crank(this is mostly used in the uk though)
fwhp/rwhp/awhp = is the actual power found at the front/rear/all wheels, not the crank
 

TBone48

Platinum Member
Feb 23, 2005
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You got it flipped- bhp is measured at the driven wheels, while hp is generally measured at the flywheel. BHP stands for Brake Horse Power.

I screwed it up, too:eek: See above post.
 

Stumps

Diamond Member
Jun 18, 2001
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Originally posted by: shabby
hp = a formula, torque * rpm / 5252
bhp = is a machine that uses a 'brake' to measure the true power of the engine at the crank(this is mostly used in the uk though)
fwhp/rwhp/awhp = is the actual power found at the front/rear/all wheels, not the crank

that sounds bout right, generall though HP (here in Australia anyway) is used as a term for WHP, but you are correct, the reason for this is that here in australia at least most of our performance cars are RWD so only the HP term is used because nobody really gives a sh*t about FWD/AWD figures...I guess it's the redneck in our culture