I apologize but I've looked and I'm trying to find out if the exhaust on a coupe is shorter/different than my 09 G37X Sedan? Any help would be great.

 

The sedan has two small mufflers, one on each side. The coupe has one large muffler with two inlets and two outlets.

Two completely different designs.

 

Can you explain what you are trying to accomplish? Several have used the Coupe midpipe on the sedan because it leverages smaller resonators and larger tubing after the resonator, but you will need to frankenfit a bit because it's designed to mate with the coupe's cannister muffler as opposed to the sedan's dual setup.