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THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHDrawbacks of Weld-on catalytic converters
Leading reported evidence
Install aftermarket catalytic converter
Performed · outcome unconfirmed
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0
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Performed · outcome unconfirmed · Original poster
Having imported a 996 to California recently, I didn�t realize the previous owner had installed an aftermarket catalytic converter.
Leading evidence: 'Install aftermarket catalytic converter' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Inspect cat' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed · Original poster
I think I�m a bit torn on the aftermarket bolt on vs weld-on given the price is double - 1400 installed per side vs 700 per side for universal.
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Performed · outcome unconfirmed · Original poster
Dealership wants $7000 for oem cat installed so that path seems cost prohibitive.
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Performed · outcome unconfirmed · Original poster
my understanding was in CA it�s illegal to install used cat.
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Performed · outcome unconfirmed
Can be done w/o jack stands (I use drive up ramps) in about 2-3 hours.
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Suggestion · Original poster
I�ve got last 10 yrs of service record for the car and looking through it I see 2 catalytic converters replaces 2 yrs ago and the aftermarket cat seems to be non CARB compliant hence causing the failed smog.
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Suggestion
If you still had the OEM units you could send them to the UK and they would cut them open and replace the cat honeycomb with 200 cell units that would pass the sniffer test and the visual (being OEM units).
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Suggestion · Original poster
Not knowing much about the emissions systems on 996, what are the drawback of weld on cat besides it being more difficult to remove and change without cut and weld - e.g would changing O2 sensor be more difficult than bolt on?
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Suggestion · Original poster
Not knowing much about the emissions systems on 996, what are the drawback of weld on cat besides it being more difficult to remove and change without cut and weld - e.g would changing O2 sensor be more difficult than bolt on?
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Having imported a 996 to California recently, I didn�t realize the previous owner had installed an aftermarket catalytic converter. As a result, the car failed the visual inspection for smog and therefor the car unable to be registered.
I�ve consulted a few muffler shops and most recommends an aftermarket universal weld-on such as walker or magma flow units . Dealership wants $7000 for oem cat installed so that path seems cost prohibitive.
Not knowing much about the emissions systems on 996, what are the drawback of weld on cat besides it being more difficult to remove and change without cut and weld - e.g would changing O2 sensor be more difficult than bolt on? I�m driving the car on the street and don�t see a need to modify cat in the near future so removal for tracking purposes isn�t a major concern for me.
thanks
I don't know if it helps but another member posted this CARB lookup list on the ARB site:
https://arb.parts/Vehicle/1999/Porsche/911
When I googled this ARB site never came up so I didn't know it existed. Very helpful because when I just googled for a cat it's pretty hit or miss but this site gives part numbers I can specifically look for. I think the OEM CAT is very similar to a universal so should be easy for a muffler shop to install with sensor access. Also, I thought if you import a car to CA you just need to meet Fed standards so I wonder if your car was a CA car to begin with.
I came upon that site searching this forum too, it is super helpful and I used it to test and confirm which part number the shop is installing. Great call out on making sure the muffler shop installs sensor access, I�ll be sure to triple check that.
As for the Fed standard, the car has an after market exhaust which triggered them to visually inspect the CAT. I�ve got last 10 yrs of service record for the car and looking through it I see 2 catalytic converters replaces 2 yrs ago and the aftermarket cat seems to be non CARB compliant hence causing the failed smog. This stuff can definitely get quite draconian, I guess it�s just the cost of living in the golden state.
my understanding was in CA it�s illegal to install used cat. I did find a few cat on eBay and thought about going that route too, the challenge is finding an installer wiling to do it.
One of the least expensive options at ~$1100 is the CARB certified Magnaflow units which they state are bolt-on replacements for the stock units. I looked at them when my cat went out before deciding I'd go full aftermarket with complete Cargraphic exhaust. The Porsche OEM units are ridiculously expensive. If you still had the OEM units you could send them to the UK and they would cut them open and replace the cat honeycomb with 200 cell units that would pass the sniffer test and the visual (being OEM units).
Yeah. I think I�m a bit torn on the aftermarket bolt on vs weld-on given the price is double - 1400 installed per side vs 700 per side for universal. The OEM with 200 cell is an interesting idea, I can source used oem cat pretty easily but am less certain about tackling the installation as I�ve never worked with emissions components on cars before.
It's one of the easier jobs other than an oil change. Can be done w/o jack stands (I use drive up ramps) in about 2-3 hours. Take off the bumper (#2 Phillips head screwdriver), remove the heat shielding (10mm socket on the sides and 5mm hex key under the bumper) and unbolt the exhaust (two 13mm wrenches for the header/exhaust point, 19mm socket for sleeve joints and 17mm for clamps at back of engine). Helps to remove the airbox (13mm socket for the airbox and 7mm socket for hose clamps on intake) so you can unplug the O2 sensors. You'll need a 22mm wrench for the O2 sensors. Use anti-seize when reassembling so nothing rusts/freezes.
If anyone is interested in a 'how-to', let me know and I'll post a step by step this weekend when I put my old exhaust back on.
I don't have direct experience with the magnaflow units and how well they fit but being in CA there aren't a lot of options. Replacing the cats is pretty easy if you can do some basic wrenching.
Here is a link to get the OEM cats upgraded to newer 200 cell units in the stock units:
http://www.carnewal.com/products/996...nge-Sport-Cats
The Dealership is on something if they quoted you $7k - the parts are about $1300.00 (that's for 2 - L & R Porsche OEM cats - they are listed for $613 ea. at Auto Atlanta
http://www.autoatlanta.com/porsche-p...section=202-00
#'s 5&6) it can't possibly more than 2 hrs. labor, plus a few ancillary parts - bolts, clamps - could this possibly be more than $700? That's $2k total - where's the other $5k? In their pockets? Hmmmm... Stealership - very applicable to this situation!. As for the inspectors... If it's a stock (Porsche) CAT how would they possibly know that you bought it used? You could tell them they're original to the car and you got them from the original owner... And why would you need an installer? It's literally 3 bolts and a clamp for each cat...
https://www.ebay.com/itm/Porsche-911...MAAOSwk3lfWVI0
https://www.ebay.com/itm/Porsche-911...AAAOSwk3lfWVEH
^^^ There's a set for $1k put the other $6k back in your pocket and move on...
For sure, I had to confirm a bunch of times he didn�t quote me the whole exhaust system. $7000 is after core return too. Stealer ship is right .
Funny cause I was just looking at those 2 eBay cats due to this forum post. Hard to tell the condition on eBay but if it works, it could be a great option.
It's called a 'Temporary Operating Permit' or 'TOP'. You have to show your failed smog test and then you can get a TOP that's good for 60 days from the date of the failed smog test. If you're a AAA member, you can get one without having to wait in line with the unwashed masses at the DMV.
I have a complete stock unit (cats and mufflers) that I just took off the car yesterday if you decide you can go the used route. Car only had 44K miles. PM me if interested.
