Cleaner aftermarket catalytic converters?

[California98Civic]

Are there aftermarket catalytic converters, or other CAT mods, than can be retrofitted to improve emissions on my 1998 Civic? On other cars? One day, my CAT will die, perhaps, I'd like to know in advance if there will be a better, Cali legal, alternative. Also, maybe at that time--if it comes--I could tune the whole exhaust system to reduce pumping losses, and rely on an improved CAT to keep me within legal emissions parameters? Does any of this make sense?

[Daox]

I don't believe there is any 'improved design' out there, they have worked the same since 3 way catalytic converters were put into use. I'm sure they've reduced cost (less precious metals) over the years. The only real improvment I'd think you can make is moving your CAT closer to the exhaust manifold if it isn't already up there. This will make it warm up faster and keep it warmer during engine off cycles.

[PaleMelanesian]

Cali legal is the sticky point. Most of the aftermarket units are not. I used the common Dorman replacement on mine, but it's not CARB certified.

It's kind of hard to get closer than our cats are already.
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