Its funny how I see a lot of people on here trying X pipes, yet say they want the classic 60s 70s sound. Your not going to get the sound you want with an X pipe. No matter what X pipe you have its going to be higher pitched then an H. The pro chamber will give you the deepest sound. My buddy has an 05 GT and put slp on with his stock H pipe and it sounds good. I would say the best sound for the s197 would be a catted Prochamber (deeper then the H) and SLP. That’s my opinion. My buddy and I compared are exhaust. His again has stock H and SLP, mine has a catted MRT H and magnapacks. His car was louder but we both agreed that my 01GT was a heck of a lot deeper then his S197. It just seems harder to get the right sound with the s197.