Contour Enthusiasts Group Archives Forums General General differce between hp and hp at the wheels,

what is the diff. between the two, is hp at the wheel not the same as torque or what. what does bhp stand for?
well someone please feel me in on this info.

HP at the wheel means on the dyno at the wheel! HP in general is rated at the crankshaft, IE as it comes out of the motor. HP at the wheel is more aplicable because it's the power you put to the ground to move the car. At the crank, you aren't going to see the losses cause by the rest of the drivetrain, ie trans and drive shafts/axles. I know the difference between TQ and HP but wouldn't be able to explain it well!

-Andy

The difference bewteen flywheel (engine output rated by the manufacturer) and the power at the wheels comes from drivetrain losses. Transmissions have friction, as well as differentials and other smaller losses. Automatic cars typically have 20-30% loss between the engine and the wheels and manual trans are in the 12-18% range.

what does BHP stand for

brake horsepower.

Means the same thing as HP.

Horsepower is the amount of POWER generated by the engine.
Peak Horsepower is usually xxxHP @ xxxxRPM.

Torque is the inverse.
Torque is the amount of RESISTANCE it would take to STOP the engine at that particular moment in time.

Most engines generate more TORQUE in the first 3000-4000 rpm band then Horsepower.
Horsepower kicks in after the Torque peak has usually passed.

To put the two in perspective...

Torque is used to propel your vehicle from a standstill to a particular speed.

Horsepower is used to maintain a particular speed.
More Horsepower Means Faster Top End Speed.

Off the line, Torque plays a major role in how fast your vehicle launches, not to mention traction.
This is the PULLING AWAY sensation you get when your first accelerate.
The higher the Torque the more you feel the car
"pulling on the seat of your pants" when you take off.

When our Duratec Engines pass throught the 3500 - 400 rpm band,
the secondary intake valves open to increase the airflow to the cylinder.
This results in increased HORSEPOWER.
This is the second wind, or second acceleration, that you feel
as the car is accelerating towards the speed of light... he he...

These terms are usually 12 - 18% less at the wheels, because of the Transmission losses.
Less for Manual, More for Automatic.

Then was is it called brake HP, what does the brake in there for

I thought BHP stood for Base Horse Power.

Technically it is all brake horsepower, they've just dropped the "brake" part and just started calling it Horsepower.

http://www.sciencenet.org.uk/database/Physics/0103/p01446d.html

If you notice, by the old method of calculating hp, a 2.5l Duratec V6 would be making 25 HP and 170 BHP. So the old method has pretty much been eliminated and BHP is used, though it is still called HP.

how are you pushing 190 hp? you are talking crank right? and im assuming that this is a guess based on what the performance products advertising has told you?