I have an 85 vette with the tpi motor. I just purchased this car as a project and have a question about the exhaust. I am looking at various aftermarket catback systems for my 85. A large amount of the systems such as the magnaflow say that they are made for 86 and up vettes. Does my 85's y pipe and muffler setup differ from that of 86 and up? If so does anyone have any recomendations on good systems for 84-85?