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 11-13-2003, 12:29 AM #1 ferrarichika CF Newbie     Join Date: Jul 2003 Location: Virginia Posts: 79 What's the difference? Just out of curiosity, what is the difference between horsepower (hp) and brake horsepower (bhp)? I subscribe to Road and Track and they use bhp measurements instead of hp and I was just wondering if there was a significant difference between the two. Thanks! __________________ "Succeed- that is the advice which falls drop by drop from the overhanging corruption."
11-13-2003, 12:33 AM   #2
vwhobo
CF's Anal Orifice

Join Date: Feb 2003
Location: Redneck Hell
Posts: 8,630
Re: What's the difference?

Quote:
 Originally Posted by ferrarichika Just out of curiosity, what is the difference between horsepower (hp) and brake horsepower (bhp)? I subscribe to Road and Track and they use bhp measurements instead of hp and I was just wondering if there was a significant difference between the two. Thanks!

BHP and HP are arrived at by taking the same measurement in a different way. You'll find if you look at vehicles that have been tested for both numbers they'll always be within about 1% of each other.

So the short answer is there's no difference in the real world.
__________________
Thanks for the pic, jedimario.

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 11-13-2003, 12:36 AM #3 ferrarichika CF Newbie     Join Date: Jul 2003 Location: Virginia Posts: 79 Oh, okay! Thanks so much! __________________ "Succeed- that is the advice which falls drop by drop from the overhanging corruption."
 11-13-2003, 12:48 AM #4 vwhobo CF's Anal Orifice     Join Date: Feb 2003 Location: Redneck Hell Posts: 8,630 This is the long answer... brake horsepower: (bhp) A measurement of the actual usable power (not calculated power) measured at the output shaft (usually the crankshaft) rather than at the driveshaft or the wheels. Thus none of the auxiliaries (gearbox, generator, alternator, differential, water pump, etc.) are attached. It is called the brake horsepower because the shaft power is usually measured by an absorption dynamometer or "brake." This is not the brake on the vehicle's wheels but a testing device applied to the shaft. This instrument is applied to stop or absorb the rotation of the output shaft and returns a value. horsepower: (HP) A measurement of the engine's ability to perform work. One horsepower is defined as the ability to lift 33,000 pounds one foot in one minute. To find horsepower, the total rate of work in foot pounds accomplished is divided by 33,000. If a machine was lifting 100 pounds 660 feet per minute, its total rate of work would be 66,000 foot pounds per minute. Divide this by 33,000 foot pounds per minute to arrive at 2 horsepower. In metric terms, it is the ability to raise 250 kilograms a distance of 30 centimeters in one second. It is also equal to 745.7 watts. __________________ Thanks for the pic, jedimario. "Everybody believes in something and everybody, by virtue of the fact that they believe in something, use that something to support their own existence." Frank Vincent Zappa, 1940-1993
 11-19-2003, 10:42 AM #5 Cliffy CF Loafer     Join Date: Nov 2003 Location: NE Hampshire, England, UK Posts: 8,442 You will also notice in some cases PS is used, which I believe is the German equivilent, I cant remember what it stands for though. Here in the UK most newish Fords have a PS measurment on the top of the engine.