I've been modifying my Evo IX SE this year after a life of being stock. The time has come to do a transmission rebuild, and i'm looking for some input on gearing and final drive options.

My initial thought has been to change out the stock (4.52) Final drive for either a 4.31, 4.1, or 4.0. following that up with a stock (2.78) first gear swap to the Evo VIII first (2.92)

Second thought would be just to swap out the 1st and 5th gears to the Evo VIII ratios.

The goal being to maintain torque and acceleration on launch with a improved 75-80mph rev count (trying to stay around 3000).

Currently 60mph in 5th gear sits at 3000rpm

Any input is appreciated!

 

How much power are you putting out?

 

Pretty conservative (amateur) tune on 93 at 330whp. Looking to get a professional tune once the trans is rebuilt and shooting for 400whp

Mod list is pretty short so far: AEM short ram intake, ETS piping and FMIC, Custom 3" Turboback exhaust, tomei adjustable exhaust cam gear, walbro 255 and my MBC is set to 22psi.

 

Stay with stock final drive. Changing it will make your car feel slow. Now if you have a built block and make over 450 ft-lbs of torque, then go with 4.31.

 

Final drive shouldn't be changed until over 500wtq, then a 4.31 is good. 4.11 is good for 600+ wtq