ok well i have a fg sedan with a gt rear bumper on it, so it has left and right exhaust cutouts on it. i currently have a twin 2.5 inch exhaust going to the right cutout. ive been to a few exhaust shops to see what can be done and they seem to follow 2 different schools of thought. idea 1 is strip the system off from the cat back, sell it, and start again. idea 2 is remove the current rear muffler and pipes, replace with a single 2.5 pipe to each side and a muffler on each side. have them come out as single pipes but put a twin tip on them. is any one of those ideas better than the other?
ive also noticed that having the larger exhaust makes the car a little sluggish off the line. is it possible to replace the current rear muffler and pipes with a smaller diameter, say like a 2 inch setup from an xr8? will it matter if the front half is 2.5 inch and then it goes to 2 inch, and how will that affect the sound and performance?

Sorry can't help much but i am interested in this to as i got a GT rear on mine and really want twin pipes but i dont want the current sound of my exhaust to change (dont think its possible though).

I to have had mixed opinions from places about splitting it (y piece) from just after it comes over the diff and having a muffler on each end. They didnt talk about removing the centre muffler and i didnt like the idea of having 3 lol

anyone?