2.5" exhaust big enough?

[sprmotohooligan]

Hey guys, searching this topic was a bit tough so I figured I'd start a new post.

I found a good deal on a used 2.5" turbo-back exhaust with a Thermal Research muffler. Now before I go spending a few bucks on this I want to know if its big enough for my goals. I'm looking to build a nice EVO III powered street car with 300 awhp by the end of summer. If my car ends up making more power then that when I have it set up good for me. But 300 whp is the goal, no more, no less.

Is 2.5 inches from the turbo back big enough to support that goal? Or should I save up some more and just splurge on the 3" exhaust.

 

[pboglio]

If you hate noise, go 2.5" and live with the restriction. Nothing beats a 3" for power though.

 

[2gawdtsi]

2.5 should be fine, 3 inch youll also gamble with boost creep.
evo 3's are notorious for boost creep.

bigger is not always better.
for your goal however I would go with 3 inch,

 

[LTUDSM]

for a 300whp dd car ,i deff would go with 2.5 exhaust.Making 300 whp with 2.5 would be no problem. 3" exhaust is more louder,and more annoying for a dd car.

 

[snakeyes711]

I'd go with 2.5", thats what I'm going for also.