What is BHP

[[GSV]Trig]

One of the chaps in the office wants to know what BHP is and what it means etc...

Come on Zak I bet u have nothing to do at lunch

[Lowe]

You want it in english or proper?

[Atomic]

BHP = Brrrm Brrrm.

eg. More BHP = More Brrrm Brrrm

[[GSV]Trig]

You want it in english or proper?

Either, both...

[dkmech]

http://auto.howstuffworks.com/horsepower.htm

[Lowe]

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.

Zak will no doubt put that into English for you - I'm off out for me lunch break.

[Lowe]

http://auto.howstuffworks.com/horsepower.htm

Good link, forgot about that site

[Zak33]

I need say no more...that sums it up.

One horse power used to be exactly that....and if it did the job of two horses....sorted...2hp.

However....it needs an explanation of "work done"

In brief...a little Ninja...and a big Sumo...both standing at the end of a long race track...with a pile of bricks to carry to the end.

3...2...1....GO...

the Sumo, who has HUGE TORQUE (like a Diesel V8) picks up ALL the bricks in one go...and waddles off...

the Ninja picks up 2 and SPRINTS like a rocket up to the end...drops them...sprints back

If the SUMO finishes the job first...he has more POWER.

If the Ninja finishes it...he has more power.

Power is a definition of getting a job done FAST.....

So a High revving 1 litres engine has high power at 10,000 rpm.....and needs a gear box to suit.

A V8 Diesel revs at 2000 rpm and needs a single long gear....

the POWER is the ability to do the job in a set time.

BUT...its so damn hard to measure

Its SO MUCH EASIER if you work out how much braking effort you need to STOP THE BUGGER

Brake Horse Power

[Zak33]

I ...er....didnt need to say more...but got...carried away
soz

[Zak33]

thought of something else.

If Trig got a different turbo on his car that blew max air at a higher revs....he'd raise the position of his peak torque.

IF that peak torque was the same amount as he currently gets...but it was at much higher revs...his BRAKE HORSE POWER would be higher....

Cos at those revs...when the braking device was put on, it would be harder to stop.

the car would be a pig to pull away in 1st , so he'd need a lower gear kit....

I'll....er...go now

[Rave]

Yes, but one French Cheval = 10BHP. Typical French arrogance. The 2CV actually has about 20BHP, in fact the 602cc cars are closer to 30BHP.

Power basically equals torque x speed. A dynamometer as I understand it measures the torque an engine is producing and then multiplies it by revs to get the power output.

Power in BHP = Torque in lbft x revs/5250. That's why if you plot torque and power against revs on the same graph with the same scale, the lines always cross over at 5250RPM.

Rich :¬)

[Big RICHARD]

P=vi
Or P=i^2r.......

Tbh

[Event Horizon]

The quick and easy answer to this is the BHP is simply a rate of doing work, it is derived from the work athe a horse could do in a given ammount of time. Torque is most simply described as a turning force, or a force multiplied by a distance which then becomes a moment.

[Byron]

They call it Break Horse Power because the friction produced by the engines mechanical parts acts as "brake" and try to stop the parts. So the BHP is the actual output power overcoming the engine friction/ or if you like, internal resistance.