Originally Posted by dwfisk
OK I see you are leaving the 2" exhaust open, my bad. I would think you need at least a 3". Look for a custom muffler shop, they should be able to cut an sell you a 3 ft chunk of 3" pretty cheap. It will be galvanized or nickel plated but its OK for the exhaust.
One 3" will give you the same 3.7 square inch exhaust area you have with the four 3/4" inlets.
You're awesome Dave! I am most definitely making all these mods this weekend. I still have other small things like door handles and latches to put on. I'll post new pics after this weekend and let you know how it went.