07mark

Did you use one non fouler per cat or did you use two per cat? I only ordered a pair from brenspeed.
If you ordered from brenspeed, did they come rwdy to install or did you have to drill any holes?

Rubrignitz

I used two per cat. With a single per side it gave me enough time to get stickered then threw a code two days later. With two per side it never throws a code.

Rubrignitz

Oh yeah and they do come ready to install. No drilling or mods required. Just stack em.

07mark

I never throw a code, only time my CEL came on was after my inspection and threw the P0420 code. I was confused because never had a code thrown while just driving my car. So I am hoping one pair will be enough to pass the inspection and not throw a code. Did you just leave them in after inpsection? My understanding that this will have no effect on the car by leaving them in.

Rubrignitz

Yeah it's ok to leave them on. Mine have been for a few years now with an emission tune. My emission
tune runs so good I just left it on. You should be ok with one set.

thewarmachine

I also stacked mine. I think I have three per cat. Only one per side needs to be drilled out. I pass inspection and no codes.