Decided to switch up my exhaust a bit, thought I’d share some findings.

I came across this very cheap kit, it’s made by Rev9, whoever they are, it’s for a Q50, almost a catback, but without the muffler. Fully polished stainless, 2.5” from the cats, into flex pipes and into a 3” collector, then out to dual 2.5” all the way back. No resonators, but the two straight sections right after the collector are conveniently 19” long, double flared, so any 19” resonator with 2.5 ID would slide right on.

Conveniently, I had a set of those, so I decided to slap it on my g37x sedan. The flanges lined up perfectly with the cats, resonators went in the collector, then a couple of 2.5” stainless 45 degree bends to the mufflers. I’m using the oval flowfx straight-thrus, with quad 3.5 tips.

Everything lined up perfectly, I get in, brace myself, fully expecting neighbors to start yelling at me, push the button, and…

… did I accidentally install my factory exhaust? It sounded good, but so quiet, I couldn’t believe it. Actually, it sounded exactly like those HKS Hi-Power axle back cannons, if you ever heard those.

So, today I decided to do the unthinkable. I pulled out the resonators and put the original straight pipe pieces that came with the kit. I was banking on the fact that those big ol’ flowFX are essentially oversized resonators. And it looks like I was right.

Zero rasp. None. At all. Very minimal drone. Screams like a banshee under WOT. I didn’t expect such a dramatic change. Cold start sounds amazing. The only thing I will do is add a couple of tiny bottle resonators, I have a set of 8” somewhere here. They are not packed, just perforated tube, but they should clean up the last of the drone.

So, there you have it. Another budget option to consider, with zero welding or fabrication. Cheers.