Borla XR-1 Muffler Size

[Nick McDermott]

Hey guys, 

I finally got good news that my truck is built and being shipped. It’s a 3500 AT4. In preparation of it arriving and wanting to swap out the muffler I have been looking to get a XR-1 but not sure what size I need. Would it be the 3.5” in and out? 
 

thank you! 

[Nick McDermott]

I should also mentioned I am clamping the muffler not welding so I need it to slide over the pipes after removing factory muffler 

[Kjduvall]

yes its 3.5 in i used the borla xr1 summit p/n bor-40086 3.5in in/out and summit p/n sum-640274 3.5in and 45in long stainless pipe to make up the space left over. and it sounds great not super loud but very nice tone and no drone in the cab (mines a reg cab). and i suggest welding it in honestly a local shop will not charge much for that, its just much cleaner to do it that way.

[Nick McDermott]

47 minutes ago, Kjduvall said:

yes its 3.5 in i used the borla xr1 summit p/n bor-40086 3.5in in/out and summit p/n sum-640274 3.5in and 45in long stainless pipe to make up the space left over. and it sounds great not super loud but very nice tone and no drone in the cab (mines a reg cab). and i suggest welding it in honestly a local shop will not charge much for that, its just much cleaner to do it that way.

awesome thank you! Do you need the extra pipe based on the size difference of the muffler? The borla that much smaller? 

[the8rotor]

I just welded in a Vibrant muffler and resonator. I cut out the center section and added 32" of 3.5in pipe between the resonator and muffler.

[Kjduvall]

yes you need the length to make up the lost length, the factory muffler is huge.