How are aftermarket CARB cats installed?

[JoeSchmoe]

I was wondering how the aftermarket CARB cats (such as magnaflow and flowmaster) mount on the car. They don't have flanges on them. Do I take the old cats to a muffler shop and have them cut and re-weld the flanges onto the new cats? Or is there another way? I also see a bolt-on aftermarket cat from DEC, but I can only find one side in stock.

-- Joe

 

[solidol]

You need to cut oem flanges and weld new cat in.

 

[JoeSchmoe]

OK thx.

-- Joe

 

[Jinks]

I was under the impression that there is no such thing as aftermarket carb approved cats.

 

[JoeSchmoe]

I was under the impression that there is no such thing as aftermarket carb approved cats.

AFAIK CA allows installing CARB aftermarket cats for emissions compliance reasons, but not for performance reasons. There's some sort of papertrail from what Im starting to discover. I guess Im going to find out the hard way tomorrow...
https://www.arb.ca.gov/msprog/aftermktcat/installcatq&a.pdf

-- joe

 

[JoeSchmoe]

After much searching and several cancelled purchases, it appears most of the bolt-on (direct-fit) CARB cat options are not CA smog legal anymore. Several shops pointed me back to either the magnaflow or walker weld-on cats as the only CA options.

Does anyone know if there is enough room between the 91-94 flanges to fit the magnaflows? The 332304/332305 bodies are listed as 11" long, which seems kind of tight with that 90 deg bend. The last thing I want is for a smog shop to take a sawzall to the tubi to make it fit... Or perhaps the walker ones would be a better match (albeit with a 2" inlet)?

Any suggestions or comments?

-- Joe