I have a question concerning chasis dyno. I was curious to see what my car really had so I forked over the money to see what exactly I had. It kind of turned out the way I expected but one thing, the gentleman who ran the dyno said that I would have close to a 30% lose thru the drive train. I have heard of anywhere from 18%-22% but nothing close to 30%. Is this accurate? have you had any exiperience with this?
here what I am running:
462cid, TH400(w/shift kit), 3.73 rear gear, with 28"slicks.
Is this just a guess on his part at the flywheel? I don't understand this big of a difference. what do you think? graemlins/thumbsup.gif

For sure it is all just a guess - only way to know for sure is to pull your engine and do an engine dyno pull. I've seen it go both ways, the torque converter efficiency has a lot to do with the results. Also, it definitely does take some power to turn over the rest of the drivetrain. My Elky's engine rang up 640 hp on the engine dyno, the chassis dyno came in at 476 hp with a torque converter that was ~ 92% efficient.

Thomas

Mike,
I was told at speed Inc. one of the countries biggest LS1/LT1/turbo buick shops that it is closer to 15%+/-. This does get a little out-of-whack if lets say you had a 12 bolt with 4.56 gears and tall heavy tires.

-Joe