EDenney

The title says it all.... I live in the People's Republic of California and I want to know if high flow Cats are street legal and if my car will pass smog with them. Are there certain brands/models that are street legal in CA and others that aren't? Recommendations?

TIA

SLPRC5

I have had mine smogged with hi-flow cats and the only thing I was told "they don't last as long as the OEM cats"..One thing to remember, make sure the hi-flow cats are heated up before the smog test is done...they take longer to heat up than OEM cats. Take car for a drive before going to the shop and while here let the car idle...
Good luck

teddyca

No they are not. They do not have a CARB sticker. It is also illegal to move the placement of the stock cats, hince the reason long tubes are also forbidden.

BlackZ06

To be legal in California, a replacement part such as a new catalytic converter must come with a CARB (Calif. Air Resources Board) "sticker" or must be a direct OEM replacement part.

There are no "high flow cats" that have a CARB sticker issued for them.

Will you pass a smog test ???

Kind of a crap shoot .... you have to pass both a visual inspection, plus an OBD2 test ..... if your high flow cats don't trigger any DTC for poor cat performance, you stand a reasonable chance of getting by.

EDenney

Thanks for the info guys, it's very helpful. Any feedback from others that live in this country within a country (CA) and actually have high flow Cats on their street C5 and have dealt with this issue? Do they ever actually DO a visual inspection realistically? Obviously every place is different, but I'm talking in general terms. I don't recall smog shops ever putting the car up on a lift (or most of them even having a lift) when they smog it. Can't imagine them visually inspecting the Cats without putting it on a lift.

Are there any high flow Cats that are reasonably assured of passing smog in CA as long as a visual inspection isn't done? Is there anything that can be done within the law in CA about the restrictive Pup Cats on the 2000 C5s that were delivered to and sold in CA? Just curious...

TIA!

EDenney

After doing a little more research on the Cat situation here in CA., I believe that Pup cats were only introduced in 2000, and in that year only to cars destined for sale in CA (I have a 2000 A4 sold in CA). Correct me if I'm wrong but hypothetically speaking, not necessarily because it would offer me a world of gains, couldn't I legitimitely replace my Pup Cats with regular Cats from a 97-99 C5 sold in CA, which would have the CARB sticker and is perfectly legal in CA? The 2000 was given a better Cam shaft to compensate for the restrictive Pup Cats apparently, so I would have the best of both worlds, and still be playing by the proverbial book .

Not to say that I'm even considering doing this, but it makes for an interesting exercise . Anyone, anyone? Bueller?

BlackZ06

There is nothing to "replace" .... the pup cats were added until the 2002 Model Year to aid in "lighting off" the cat system as early as possible in a cold start situation. All 2001 Corvettes had the pup cats to meet Federal law .... CA was a year "ahead" .... with the 2002 Model Year GM shifted to a cat material that lit off quicker, allowing them to drop the pup cats. The cats you have are the same as from 1997 .... the law changed for 2000 requiring "cleaner air" on a cold start ... so the pup cats were added for two model years .... eliminating them does nothing for your performance ... they are simply there for cold start situations.