Converting BHP into MPH

I'll assume "BHP" means "Base Horsepower" and if that's the case it's a bit of a side issue in calculating MPH.

What's most relevant is engine RPM. If you have the engine output RPM you can calculate the RPM through the transmission gearing, the differential gearing and then based on the tire diameter you could calculate the MPH figure.

The Horsepower rating is more important in figuring how much weight can be moved as opposed to how fast it can be moved.

I stopped studying physics ages ago, but I will give it a go

Force = Mass x accerlation
Work = Force x distance
Power = Work/time

Hence

Power = (mxaxd)/t
= m*(d/t^2)*d/t
= (m*(d/t)*(d/t))/t
= m*s^2/t

Where m = mass
d = Distance
t = Time
s = speed

Plug in the numbers and voila !!!

Ofcourse, I maybe totally totally wrong !!!

ANy idea where power output in kW comes into all of this?

Thanks for answers, BTW. I haven't got any data yet to test them with but I'll come back once I have.

1 hp = 746 Watts

http://search.able2know.com/Shop/Auto/Horsepower_Calculator_L1227/

Hi, i just joined able2know to contribute to this forum...

So, Grand Duke, it IS possible to calculate the max velocity of a car using BHP... but u'll need to know the aerodynamic coefficient of the car... the weight doesnt get into top speed... but top speed (or terminal velocity) is reached once the output power (BHP... Brake Horse Power... not Base) is equal to the drag (Drag is proportional to C.v^2 where C is a constant related directly to the drag/aerodynamic coefficient sometimes quoted in car reviews)

Fishin'... its theoretically possible to calculate the max speed using the rotational speed of the engine in rpm, knowing the gearbox ratio, and the wheel to gear ratio... its more accurate to say that u can find the speed at any point using that method, but not necessarily the top speed! unless you actually drive your car to its limit and check the tachometer to see the RPM, then yes it'll be posible... (as long as your clutch doesn't slip that is! )

Gautam, your first 3 equations are correct... but a=(d/t^2) is incorrect... nice try i must say! but the mechanics is much more complicated than that cos the acceleration is not constant!

I hope all of this helped you guys out... its just a little of what i learnt at uni... currently reading mechanical engineering!