I have an LT1 in my IROC and I just installed a set of Hooker LT's. I want to run an X pipe with dynomax bullet mufflers. I'm thinking that if I go with 3" that it will not create enough back pressure. The LT1 is mostly stock for now, but I do plan to run mid 12's with it. So, give me your opinion on what will be best. Thank you.

 

If you're tight for ground clearance... I'd go with 2.5".

But if you are planning more power in the future... then 3" sounds good.

 

I wouldn't worry about the backpressure issue, 3" will work fine.