I am running 5AT, and now saving money for FI. but before that I am thinking maybe I can start to do some small upgrades before FI, such as cat/back exhaust system, popcharger, and Plenum Spacer ... etc. Can someone tell me what kind of upgrades will be still worth when I go FI?

 

I'm not sure what they do but the AT guys have something to make the tranny hold more HP and shift quicker. I think it might be a service someone offers. Buy a new plenum, and focus on other things besides engine. You will need beefy new tires, and a big brake kit will be good to have. New coilovers, Maybe a body kit if you'd like. Be careful with exhaust, you will need a large free-flowing exhuast made for turbo. Such as a 3" single or 3.5", which will hurt horsepower on an NA car. So you could buy one now if your planning on FI soon if not just keep the stock one for now and just buy test pipes.

 

There are many dual 2.5" exhaust systems that will make power NA or FI.
A dual 2.5" exhaust has the same total flow area as a single 3.5" exhaust, so you could do either with approximatly the same results. And either would be very helpfull FI or NA.

Test pipes are certaintly possible too and they'll make more power for either setup.

 

Invest in a brake upgrade, then suspension.....not necessarily a BBK but something like Stoptech's stage 2.....then sway bars.

 

Thank you, guys! my car is Track mod with brembo break, does it still need to upgarde? so, popcharger, and Plenum Spacer will all do fine?

 

Popcharger will have to be tossed when you go FI. UNless U go JWT then you will simply have an extra that you can clean and put on a fresh intake every oil change. I reccommend suspension, Exhaust and a plenum spacer. All fun and great mods and a definate necessity when going FI.