by Fletch » Wed Mar 23, 2005 1:36 pm
Sorry I don't have the #'s to back it up, but for biggest 1/4 mile improvement go for a custom cat delete y-pipe. It may be a bigger bottleneck then the air intake because the rear bank has to come forward to meet the front bank. That type of design is for low end torque which you don't really want for drag racing anyway.
I have noticed that I am able to shift quicker and more reliably from 1st to 2nd with the high flow y-pipe also. Not as much back pressure on the engine. My 2nd gear synchro is a little beat up, so that 1-2 shift used to like to grind at me every once in while, awful sound.
Just swap back stock to pass emissions if neccessary.
2006 Legacy GT spec.B
(Totaled) '99 SE V6, TRD S/C, 5.5 psi Pulley, Jim's Fuel Upgrade, TRD Shortshifter, SPEC Stage 3 Clutch, Lightweight Flywheel, Tokico / Eibach, TRD RSB, 2.5" Custom Y-Pipe, Greddy Cat-Back