2.5"=>2.5", 3.0"=>2.5", or 3.0"=>3.0

[swiff]

i plan to use a magnaflow muffler when i rework my exhaust set-up. i have a 2006 silverado with the lq9 engine. nothing else yet. what muffler pipe size should i go with? i also plan to use one of the magnaflow dual-in/dual-out mufflers with the built in x-pipe. it would probably be a dual rear exit or dual exit before rear wheel.

what size pipes/muffler should i roll with?

i dont have any major plans either, just exhaust/intake/tune etc. cam and headers would be a long way down the road. thanks guys.

[RedHeartbeat]

I would think you would want to run whatever size pipe is at the manifold. If you start with a smaller pipe and then make it larger you will slow the gases down but get a deep rumbly sound. If you start with a large pipe and then go smaller you will restrict the flow. Have you measured the diameter of the pipes up front?

[swiff]

well, i think the pipe going into the muffler is 2.75". then the dual i/o muffler with 2.75" goingto an y-pipe and then exiting with a 3.5" pipe.

so i'm thinking of using the 3=>2.5 muffler. it should easily weld onto the stock pipes. then have some new 2.5" pipes bent.

i think the stock system is similar to the Silverado SS and VHO trucks. this is one of the new vortec max's.