Dumb question
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From: IN (may-oct) FL (oct-may)
Dumb question
I admit, I'm not a mechanic, I can barely change my own oil!
My question is, will my 3.90 rear end have any effect on dyno numbers vs the the numbers with the old 3.42's?
My question is, will my 3.90 rear end have any effect on dyno numbers vs the the numbers with the old 3.42's?
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Joined: Dec 2002
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From: Lakewood Ranch, FL
Yes, it will be less. Phil at DTE has a great explanation for the technical reasons - which I promptly forgot. Something about how quick the drum spins up on the dyno.... It only affects measured HP not real HP.
Last edited by johnodrake; Jul 12, 2007 at 10:42 PM.
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From: IN (may-oct) FL (oct-may)
ok, then if that's true,
would a broken in (LPE) engine develop more power than a green engine, and if so, would that be enough to compensate for the loss in power due to the lower diff ratio?
Drifting
Joined: Jul 2003
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From: Annandale VA
"Green" engines are usually a bit down on power for two reasons: one is that the engine is a little tighter in clearances, but the rings may not have fully seated. The other is that the ECM is still in its learning mode. There are some anecdotal reports that the ECM programming is designed to keep the power down a bit for the first 5K miles or so, but I haven't seen definitive proof. There are many reports of engines "waking up" after they are fully broken in.
Last edited by HITMAN99; Jul 13, 2007 at 09:55 AM.
