RE: Updated HP vs Speed

Frank Marrone (marrone(at)wco.com)
Wed, 11 Mar 1998 08:01:40 -0800

When I was researching this topic most material I found claimed that transmission and differential efficiencies were more like 80% to 90% EACH! Typical drivetrain overall efficiencies (including a little bit for rolling losses in tires) were around ~75%.

Also note that gear loss efficiency is kinda porportional to transmitted torque and bearing and tire losses are kinda porportional to rotational velocity of the element.

At 07:42 AM 3/11/98, you wrote: >Since they are
>purely mechanical, then the efficiencies should be pretty high, maybe 95%
>each? If so, then the crank HP is about 10% more. As to SAE or DIN, you'll
>have to figure that out.
Frank Marrone MK I Tiger B9471116 marrone(at)wco.com '97 Crown Vic LX Yamaha Seca 900 (aka XJ900RK) '79 Spitfire '88 Nissan 4WD p'up