I still have the cat on mine. Don't want to fool with changing it for e-tests. I've done that before on my SC and it isn't much louder just more work than I want to do. Will probably go with Fabspeed hi-flow cat when/if this one dies. Roger

 

Got mine on last Sunday. I just worked my way around the flange and stretched it by clamping one of the rings to the inside of the pipe and working it with vice grips. Got the ring to barely fit in there and got it clamped on. There is a bunch of built up weld inside the pipe that I will probably grind off soon. Mike was right. Very Ferrari like under load! I'm wondering if the slightly smaller pipe is more restrictive though. To me the car feels stronger at low-mid revs but possibly a bit weaker at the very top of the powerband which seems to make sense with the smaller flange. Kind of disappointing quality for Borla but the price was right and it does sound terrific. I also have the stock cat still. Might go for a bypass at some point.