im once again resuming work on my 86 z28, but im still mostly at the tear down as i dont have any money yet to build it the way i want it. however, i want to do a custom exhaust, and im looking for only the cat to muffler pipe. my stock one is 2 3/4" (who would have guessed?), but im going to need at least 3" or maybe 3 1/4". my plans are for a 400hp 350 tpi setup. im not running a traditional cat back exhaust, however something a little different. i dont need to comply with emissions, it just need to look like it has a cat. im planning on using a moroso spiral flow muffler where the cat used to be, and it just splits to duals where the factory muffler used to be. there will be sufficient back pressure with the slightly smaller pipe towards the rear, which also keeps the velocity up as the gasses cool.

if i cant get just that pipe, does anyone know how much it would run to get one custom bent for me, or how often an unused muffler and tail pipes resell on ebay for?