[tomato lover]

I have never had the dreaded P0420 code for possibly bad catalytic converter. Some people online have commented that non-OEM converters may not last. Living in the original CARB state of california I was wondering if anyone had any experience with the longevity and effectiveness of these more stringent catalytic converters? One local guy that has to use OEM converters for Toyota Prius's said they have can recommend Walker and Magnaflow Calif. approved applications. I would appreciate anyone that has had working opinions with aftermarket converters. Thanks in advance.

 

[dezldave961]

I've ran a Magnaflow 3" one before in an aftermarket downpipe, and it seemed happy for the 1-2yrs before I went to headers/no cat (minimal/no inspection states). I may have had the PCM tuned to ignore codes by that point, though (an O2 bung extension could help you there). The cat itself was fine, as their stainless construction seems robust enough, so it's a matter of how much cleaning it does. Our engines are fairly clean burning when running right with good plugs and such, so you might be fine.

It's definitely not a situation I'd envy tip-toe'ing around in. At that point, I'd just be building something for track/off-road use only, so restrictions didn't handcuff me... but I understand the desire to tinker.

- Dave

 

[J.Knight]

I too ran a magnaflow 3” HM. It was essentially the cat they listed as a replacement for a 3/4 ton pickup with a big block.
It lasted 2 years before the stone came loose and rattled. And as mentioned my car runs clean like most 3800’s. It actually passed a tail pipe test with the cat gutted and and O2 emulator in the rear.
That is what I suggest to buy to keep the P0420 under wraps and the factory cat should be clean enough for a tailpipe test for a decade still. Hopefully someone still sells the emulator for our cars, mine I got from ZZP I believe.