did you guys pass smog after putting in the Car sounds Cat?

 

It would depend on whether your car was running correctly in the first place, and what your mods were.

 

I'm running a blower, heads and cam and mine passed smog with a Carsound cat. They're not as good as the stock GM cat, but they're a lot smaller, better ground clearance for a lowered car and a hell of a lot cheaper.