: Drivetrain Efficiency

09-07-08, 10:30 PM
Whats the Drivetrain Efficiency of the N*?
AKA the drivetrain loss of a 2003 Seville STS and a 1997 Eldorado ETC...?

09-07-08, 10:41 PM
ive found numbers rangeing from 20-28%
i was assuming a 25% loss with the 4T80E....

09-08-08, 08:12 PM
GM autos tend to be pretty good about not eating power on the way to the wheels, and in FWD configuration 15-20% is usually a fairly acceptable average, probably erring more towards 20% if you want to feel better about your dyno numbers vs. your crank hp.

Or dig up some dyno numbers on STS/SLS and see what they put down to the wheels (assuming SAE corrected numbers). If it's rated at 300 and puts down 240, you can assume a 20% loss.

09-13-08, 12:16 AM
Caddyinfo had a bunch of dyno runs, the were mid late 90s and if the 300HP rating was 'certified' then they were putting out in the 21x-23x which is a 20-28% loss...

09-14-08, 12:20 PM
SAE "certification" didn't start happening until around '05ish though.

There have been instances of cars not really making the power they were rated at. The '99 Cobra comes to mind...

09-17-08, 09:08 PM
i believe thats why the 05 Deville DTS is rated at 292 HP not 300 like the 00-04 Deville DTS....