I picked up some headers for my 89 iroc for free they have the air tubes, which was an awesome deal btw, they didnt have a y-pipe for it, im going to run true duals with an x-pipe, i attached an images to show you something what i had in mind i have the slip fit connectors for removal/installation of cats whenever needed... and a little bit after the cats would be an X-pipe with duals all the way back over top the axle with two flowmasters super 40's right at the rear of the car. my question is should i run it they way it shows in the picture with the left hand header running to the right side muffler and the right hand header running to the left side muffler to equal out the length's of the two pipes, or does it even matter seeing as there is an X-pipe in place??
EDIT: the pipes would be running in a somewhat stock place

anybody?

I wouldn't think it would matter with the x-pipe being there, but I don't know for sure. If you haven't done so, do a search..... someone around here has a set of flowmasters mounted in the back like that. I have some 1-chamber flows mounted in the back there too (not dual pipes all the way though). I've been curious about those super 40's since I saw them on their website. I wonder what the difference is.

ok, i just got another idea... what if i was to run a singe 3" pipe all the way back over top and right after the axle (stock pipe location) and then break off into two 2 1/4" pipes in to two seperate Flowmasters, would this make a different sound and performance change then what i originally had in mind or would that just be Ghey? cuz it seems like the single 3" all the way back would be like a really long x-pipe.....

Running just one larger 3 inch pipe and branching off will sound more uniform than running true duels and haveing the alternating sound coming out your pipes but i think if you ran duels and put the x pipe in there it would make it sound more like the 3 inch pipe but you will get less back pressure with the duels and x pipe than the single 3 inch IMO