Well im hoping to run 2.5 inch back then IDK about true duals or Fakes, but to 3" Duals out the back. WIth FLowmasters.
Oh yah and my buddy has some headers from a 350 he said he would dig up for me, slightly used, he didnt say a price but prolly not too much. SHould fit right? Or no.
If full dual exhaust with headers, run 2.5" from the collector all the way back. The engine you're using will not need more than that.
If headers to y-pipe and single, run 3" from the y-pipe joint back. A single 3" performance muffler of your choice will work fine.
BTW, been reading this thread from the start, and I like the 400. Really for your useage and the way it's more of a 'stock build' on the engine, you'll be very happy with it. Can't really beat the price too.

