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MagnaFlow Has the Answer to California’s Smog Problem

Posted in How To: Engine on September 19, 2017
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Facepalm. You know what that means, don’t you? That’s when you encounter something so stupid your only recourse is to smash the palm of your hand onto your face in frustration. Take our 2001 Tacoma project. When we brought it into California from Massachusetts two years ago, part of that undertaking was a full smog check at a California state-run facility. They popped the hood and made sure we hadn’t installed an 8-71 blower or nitrous or water-meth injection on the little 2.7L four-cylinder. They made sure the gas cap sealed and that the fuel system could hold a vacuum, and finally they stuck a probe up its tailpipe and made sure the emissions were within California spec. The bone-stock little Tacoma passed with flying colors, barely blipping the emissions output needles. But two years later when we went in for our biannual smog inspection it was a different story.

“Sorry, this will not pass because those catalytic converters aren’t legal here. They have to have a California Air Resources Board number on them.”

We argued, “But it passed the sniffer test just two years ago. And it’s not even a California vehicle to begin with. Just hook it up; it’ll pass emissions.”

Then came the facepalmable reply of the century. “We don’t care what comes out of the tailpipe anymore as long as all the emissions devices are present and correct. We don’t even measure the levels anymore.”

So, with nothing but logic to back up our argument, we threw in the towel and headed to MagnaFlow’s website for some good, high-quality California-legal catalytic converters as a remedy for the bureaucratic-induced facepalms. We found a pair of high-quality direct-fit factory replacement cats with the correct C.A.R.B. stampings that dropped right in place of our old Federal emissions-spec cats. Seemed superfluous to us, but if you have local smog laws to deal with, take some tips from MagnaFlow on how to select the right units for your vehicle and go with a high-quality product that will not give you any problems, will not fail over time, and will keep the smog monkey off your back.

When identifying which 50-state-legal catalytic converter is correct for your vehicle, check the emissions label under the hood and find your test group. With your test group in hand, you can check MagnaFlow’s website at, select “Search by Engine Family Number (EFN)”, and enter your test group to see the correct part numbers for your vehicle.

For our application, the correct catalytic converter CARB number for our vehicle’s model year and test group was D-193-103. This number has to be present on each aftermarket replacement catalytic converter installed on this vehicle in order to pass inspection.
Likewise, our pre-cat had to be replaced with a new unit from MagnaFlow that displayed the (particular to our application) D-193-103 CARB number. The MagnaFlow cats are high-quality units with catalyst material that will not dislodge or come apart in short order like some cheaper imported replacement parts you may find at your local auto parts store.
Compared with our old Federal Emissions-spec cat (above) the MagnaFlow 50-State-emissions pre-cat had a slightly different shaped canister, but the MagnaFlow unit’s O2 bungs and mounting flanges all fit like a factory-issued glove.
Likewise for the main cat, the 50-State-emissions MagnaFlow version has a slightly different shape and size than the Federal-emissions version (top), but the MagnaFlow hangers and flanges were identical to the parts that came out.
In all, it took about an hour to bring our exhaust into California compliance. It can always be a little nerve-racking to crack into a rusty factory exhaust that doesn’t leak, but the gaskets MagnaFlow included with the replacement catalytic converters are high quality and we had no leaks or issues after the installation. Plus, now we will pass our biannual smog visual inspection.


MagnaFlow Performance Exhaust
Rancho Santa Margarita, CA 92688

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