Are you doing a downpipe, midpipe and catback? Do you have a tune?

 

So for the exhaust I meant a catback, sorry for not clarifying. Though I am planning down the road to get the PRL high volume intake and a tune(idk about a downpipe yet), I would like to know if a 3in catback negatively affects stock torque or HP.

 

Additionally, I want to note that on the MAPerformance catback after the midpipe, the piping goes down to 2.5 inches after the Y pipe if that info is of any use. I'm sure brands like this would put enough research and development into their products to ensure proper performance.

 

Exhaust back pressure doesn’t matter much for turbo cars. I’d be more concerned with boost creep from going too big, or the exhaust sounding like 💩 in general

Additionally, I want to note that on the MAPerformance catback after the midpipe, the piping goes down to 2.5 inches after the Y pipe if that info is of any use. I'm sure brands like this would put enough research and development into their products to ensure proper performance.

I wouldn’t be so sure of that. Their objective is to make a system that a. fits, b. sounds louder and c. shows an improvement on a dyno. They don’t know or care if it affects anything else negatively because they aren’t going to be the ones footing the bill if something on your car breaks as a result of their “off road use” parts

 

I would think 2.5 would be more than adequate enough for that displacement. I'm running 3in on a 460 cubic inch motor with a three and a half inch tip. It sounds good but it's a big block 7.5 L. Heck you could probably get away with 2 inch on a 1.5 L. Yours being forced induction I'll second that watching boost creep recommendation. 👍