So first off I'm new here so not sure if this is the entirely correct section, hope it is. (also new to modding out my own vehicle)

Anyhow, i have a 2011 G37xS Coupe. I am looking swap out the exhaust for something that is going to give me a deeper but still refined note (not the hot pop noise out of every tuned civic on the road), and before i go though this adventure, i wanna make sure I make the right choice on this. Really my big question is how far back on the exhaust should i swap? Cat back? Axel Back? Full exhaust system? I would love to go full exhaust and get some performance but I am concerned about throwing engine codes on a high flow cat. Does the G do well with a high flow cat or are the stock 2.5 on the coupe solid enough that a cat back is fine.

 

Stock cat vs hfc depends on your power expectations. Otherwise, it's about noise. Plenty of posts here about tips/axle-backs/cat-backs. Also check the stickied threads in the coupe and sedan forums.

Welcome, that's quite a rabbit hole you're eye-balling...