4.08 or 3.90 gear questions...

tranceformer

The price depends if you end up buying all the bearings & seals etc with the gears. I've seen the gears go for $500 alone, and I've seen full install kits go for up to $900. Installation would probably be a few hundred bucks.

1/4 mile time improvement? After 2 nights at the track w/ the 4.08's, I haven't been able to beat my previous best of 12.89 @ 107 yet. Still figuring out how to launch the car with the gears, tires and alignment.

MPG loss on the highway? I went on a roadtrip as soon as I got the gears done. I averaged 22.9 MPG over the 400 miles, mostly 70mph driving. Usually I can average 24 to 25 MPG driving 70+ mph. So yes, you lose a few MPG's on the highway. How much exactly depends on your driving habits.

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Ray
2009 370Z Base Sport 6MT / 12.860 @ 109.09mph / 1.921 60ft / street tires
official 1/4 mile track times

marks370

Hey man quick question does your SRM and cruise control still work with the 4.08 FD?

derraj06

Don't think you're going to get most of those posters to answer given how long ago this thread is from.

To answer your question, the SRM requires a re-calibration via ECUTEK or Uprev to consistently work with a 4.08 FD set.

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DeliriousClam

Only issue I've had with SRM since going to 4.08 was it's off by like 200 rpm. Still works fine though

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Stillen, AAM, Shine Auto, Fujimora, Swift, EVO-R, Carbon Fiber Element, Nitrous Outlet
MECP Advanced: CEA26671
Most of what I post here are artistic works of fiction and falsehood. Only a fool would take anything I post here as fact.

derraj06

Track guys have had it randomly turn off. Being off by 200 RPM also isn't ideal. Shouldn't hurt a street car however.

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