Clearance issues for one, and you have to realize even on a turbo engine you can go too large depending on your engine and what rpm you want to make power.
Clearance issues is true...the best turbo exhaust is no exhaust though. There is no such thing as too big when you are dealing with turbo exhaust...Of course you probably wouldn't gain much if you are making less than 300hp. It would probably spool a bit faster is all.
Clearance issues is true...the best turbo exhaust is no exhaust though. There is no such thing as too big when you are dealing with turbo exhaust...Of course you probably wouldn't gain much if you are making less than 300hp. It would probably spool a bit faster is all.
I would have to agree with all of the following. You would probly need around 500hp to really see a gain in a 4" exhaust other than the quicker spool up Stinger mentioned. After that the only thing I could think of is it always falls back on how much money you want to spend. If you got enough money, clearence probly wouldn't be a issue since you could aford the oval shape NASCAR type exhaust in a 4" dia Now that I think of it this local that has a 9 sec SVO runs a 3.5 exhaust, check out his car at around 700rwhp