I have a Warpspeed y pipe, hi flow cat, and a 5.5 muffler that I want to put on my car running 2.5 inch pipes. The mechanic was telling me that I should get a different muffler because it's stock and how I should have more back pressure. Which I know is bs because I looked it up with help from you guys. I think he tried to get over on me because somehow he went from $500 to $200 I told him I don't want him to work on my car and he went on how he been doing this for 50 years etc. Anything wrong with this setup ?

 

Bump

 

I dont know, the 5.5 muffler is a 2.25" inlet so that's going to pretty much make a bottleneck effect with the rest of the 2.5" piping.

 

What's the point of the 5.5 muffler? Get a 2.5inch muffler from Vibrant Performance and call it a day.