i have an 80 trans am that i'm looking at buying a dual exhaust for. the system i'm looking at comes with either goerlich turbo mufflers or goerlich race mufflers. it will be used with a 455 with a RAIV cam, 9.5:1 comp, and longtube headers. the system has an x-pipe also. i've never heard of these mufflers and was wondering how they would sound and flow.