Just found out that my muffler has like 3 holes in it on the bottom for whatever reason. I am looking to buy a Vibrant Muffler. It's my first time buying a muffler, atm i have a 2.5 straight pipe. Do i buy the Vibrant muffler with an inlet of 2.5 or do i get a smaller inlet of 2 1/4? I am a bit lost first time ever buying a muffler alone.

 

Usually, just get a coupler for the 2.5", clamp or weld it and call it a day. If anything, get a slightly bigger tubing on the receiving,... so that your exhaust pipe goes into the muffler, and the flow isn't obstructed. Whereas if you allowed the muffler side to go inside of the exhaust pipe, you would be obstructing flow. Go with the flow,...also, don't make your car sound like a fart.

 

most universal mufflers are designed with a slip fit over the indicated size of pipe. for instance a 2.5 in. oval muffler would slip over a 2.5 in. OD pipe, the muffler itself is made of slightly larger tubing.

so the answer to your question is to get a 2.5 in. muffler and the clamp of your choice. i prefer the lap joint style band clamp as it doesn't deform the tubing. Summit racing has them for $8. they go for twice that at most auto parts stores.