I've had my CARB Magnaflow cat /w precats deleted since 2008 and I've passed CA smog with it and last year blew through AZ smog with HC + CO. My NOx was high due to blocked radiator...high combustion chamber temps.

Keep the oil consumption in check and there should be no reason a CARB cat should not last 7+ years. Sure, not as long as the OE 20 years, but paying $2k for a Genuine cat (priced via parts.com right now) vs $150 for an aftermarket Magnaflow. Doesn't make logical sense at all.

Here were my AZ smog results:

300TE // limit // result
HC: 0.18 // 1.60 // PASS
CO: 0.69 // 15.00 // PASS
NOx: 2.38 // 2.50 // PASS

So my experience has been the same as Merkey's...Magnaflow is a GO!

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