Real HP loss numbers

[Clarence L.Snyder]

> just estimate how much torque it takes to compress a valve spring
> multiply x 1/2 revs x # springs X length of valve travel x
> x losses in the vlave gear and add in the amount that it takes to
> move the valve train components around
> 15% sounds reasonable
> on 300 HP that would meav that another 52 HP was being eaten by the engine
> to move the valves
> 
You forget the valve spring also accelerates the cam as the valve closes
- gotta take that into account as well. All is not as simple as it
looks.

The Electric Vehicle conversion guys figure front drive transaxles to be
91% efficient, crank to pavement. Bevel gear transaxles, like early
tercel, LeCar, Beetle, etc, about90%.Typical read drive, like a pinto,
chevette, rear drive corolla, etc, 82% in other than direct, and 85% in
direct drive (4th of a 5 speed) This is with manual trans. From my
experience I'd say that was very close. (128 Fiat coupe with 6 HP
converted Aircraft Generator)