I'm running a big 16G with an evo 3 manifold and O2 housing and a 3" turbo back exhaust that I made. It is made from stainless mandrel bent tubing. I am running a Flowmaster which I didn't think would be a great muffler for this car, but it actually sounds ok and doesn't seem to be holding too much back!
I will have to admit that I did se temps barely into the 150's tonight for about 4 seconds....The did come right back down to the 120's and were back to the 90's once I exited the interstate! A little higher than I would like, but it takes the car into full boost in 4th to get them this high......
I will be working on this. I'm thinking of a puller fan and some insulation around the intercooler to keep the heat from the radiator from getting to it.