A 2018 US spec car should be relatively well sorted from new with no big recent changes. The X-Wedge engine is only about 10 years old from a production point, if not basic design. When I said to dump the fishtails I was referring more to the system they are attached to, the standard exhaust system is very restrictive and should be replaced by something free flowing. You can put the fishtails on the end of a free flowing system and have a pretty, efficient exhaust.
It was Draggin (Kirk) I was thinking about Chris.
