I was curious how restrictive to gains a 63mm T1R single exhaust would be? Would it be well worth it to get a 70mm?

 

Yes, get 70mm for F/I.

 

even for the greddy kit, it will be worth it?

 

up

 

I don't know if I would bother with the greddy, you'll probably have boost creep issues.

 

i saw thinking high flow cat and single exhaust, you think i'll still have boost creep?

 

Friday already huh?

 

70mm even for greddy. I had 63 J's with high flow cat with Greddy turbo kit & it really limited the power. I opened it up with HFC & Greddy 70mm single & it made a ton more power. I did have o port my wastegate with the 70 & HFC though.

 

It may be cheaper just to get a HFC or TP if you like the exhaust. You can do it either way, get a larger exhaust and run a cat or HFC. Or get a more restrictive exhaust and run a TP. Since your in NJ you will have all 4 seasons so keep that in mind. So one set up may work fine in the summer but spike bad during the winter or real cold nights.

 

i'd prefer to keep my stock exhaust and get a HFC but i really want to hit approx 300WHP is it possible?