cleanest hi-flow cat

[Craig 94 TA GT]

Does anyone know which cat is the best quality (in terms of not failing the smog) while having good flow? I originally was looking at Random, but read that Kevin's failed quickly due to poor quality. I also see that Catco and Carsound are pretty cheap, but some question their cleanliness and longevity. Pacesetter also has a 3" for ~$140, but haven't heard anything about them. The reason I'm concerned with the cleanliness is because I don't think I can pre-test with the new "Smog II" check. And I think I just read that the CA 30 year car age smog exemption is out the window. All cars made after 197* must pass a bi-yearly inspection from now on...that's at least what I heard
TIA

[Jeff_in_Atl]

I ran a pair of Thrush "high flow" converters on my 85 Mustang GT for over 10 years. The last year I had it, it passed emissions better than the first year I had it inspected in 1987 when it was stock. No rusting problems. Back in 1990 when I bought them they were $70 a piece. I got them from JCWhitney to.

http://www.dynomax.com/super.stm

[Craig 94 TA GT]

Thanks for the info Jeff. The only thing I'm worried about is that the application guide says "Except vehicles licensed in California" for the '94-'95 f-body. I wonder why it would say that because the of the top of the app guide gives the CARB qualifications.

[ryan34]

Doesn't CA say that you can't touch the stock cat unless its faulty? I don't know for sure but could be a possibility.

[Craig 94 TA GT]

Acutally, I've heard that that's a Federal law, but not 100% sure. But I've also heard that if you have over 50k, or your current cat is faulty, you may replace it. So I'm not sure of the actual laws. I'm replacing mine for 2 reasons...getting the new headers and y-pipe, and my current pollution readings seem to be increasing since the last time...particularly the "NO ppm". Also, I'm almost at 109k.

[Z Ya Later]

Not sure if this is CA or Federal law, but if the cat is 5+yrs. old, has 50+k mi. on it or is faulty, you may replace it with a street-legal OEM unit as long as the position of the cat is not changed.

[Jeff_in_Atl]

Thanks for the info Jeff. The only thing I'm worried about is that the application guide says "Except vehicles licensed in California" for the '94-'95 f-body. I wonder why it would say that because the of the top of the app guide gives the CARB qualifications.

It probably means they didn't want to spend the money to get it CARB (California Air Research Board) certified. It has to be CARB certified to be legal in California.