Ok, so I know ISR headers will fit on a awd sedan, but what about a coupe? If it makes any difference, I have a 2014 Q60S, not a G37X. I’ve read many different things and want to be sure they would 100% fit an awd 2014 q60 before purchasing, and will i need to purchase more parts or is all i have to do replace the oem headers, i have seen some saying you’ll need an o2 extension and or motor mounts

 

The ISR longtube headers will also fit G37 coupes and 2014-2015 Q60 (V36 body).

 

I have a 2010 G37x AWD Coupe and yes it does fit perfectly in our cars.

 

And yes, you need to extend the O2 harnesses
I spent the extra $ to have mine ceramicoated
Helps keep the heat out of the engine bay
And away from your right leg

 

yes DO NOT CHEAP OUT and not get the extension harness. You will in fact need it.