Would stock catalytic converters from a 2014 370z fit on my 2007 Infiniti G35 sedan? I went to my local Infiniti dealership to do some cross referencing of the part numbers, and they are in fact different. I was under the impression that all of the HR's have the same exhaust and cats. I'm not interested in high flow cats or test pipes so please stay focused on the question.

 

They are probably internally the same but have different mounting points. The Test pipes Im Running dont have any Mounting points to the chassis (the factory cats on the V36 does). The part I'm using is for all 370z/G37/V36 G35 models with the HR but I imagine the packaging and mounting points (not on the cat but brackets it attaches to) are slightly different in some way.

I bet you could modify it to make it fit, but honestly hunt around the marketplace on myG37 or ebay and I guarantee you'll find stock V36 G cats for cheap. My exhaust was hanging too low and would scrape on things before I found a way to weld it up and clear speed bumps and driveways etc. Point is you definitely want some sort of mounting hardware so it doesn't hang low, its a PITA.

I am by no means an expert but I've been around the block a few times and that's my best guess as to why the part numbers are different.