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Porsche parts - used/salvage

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I am looking for a new set of cats and have been considering used/salvage if the circumstances are right (low mileage, etc) -- if not I'll go new/OEM. Fortunately my cats are marginal so I have a little time to make a decision.

Doing a search I turned up:

1. Oklahoma Imports

2. DC Auto

3. Parts Heaven

4. There were a couple others that looked smaller but they didn't pickup their phone when I called (so that indicates to me they either don't have their act together or aren't really professional and i don't want to do business with someone like this)

Just wanted to ask the community here if I'm missing any others I should give a ring to. Also any opinions on these shops respectively would be much apprecaited. Oklahoma Imports seems very good to me. They said if they had the cats in stock they would be ~ $275ish. DC Auto had them in stock but wanted $750 each (had 40K miles on them). My car is a 3.6L but he said they get $600/each for the 3.4Ls all day long.....which I find a bit hard to believe if Oklahoma Imports is selling them for less than half that. Obviously mileage on the cats has to factor into the price, but still......

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Thanks for the response, Loren. Ya, I like the guys over at Oklahoma Imports and I have bought some small stuff from them before -- very straight shooters on those transactions. Your later point is also very well taken and understood -- however, if I could in fact pick these up for $500 for the pair it would be well worth the risk vis-a-vis $3200 for new ones. Thanks.

Edited by ferrugia
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Thanks for the response. Yes, I definitely did consider eBay but no one is selling the ones I need for an 02C4S and when I checked the completed items history I don't see any that have sold recently so I wasn't holding much hope in waiting. It's a good thought though, so I apprecaite your input.

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Personally I would recommend going aftermarket as long as you aren't concerned with keeping the car completely stock. The stock cats are known to break and rattle if you stress them out on a track day.

Mine died last year and I decided to replace them with an X-pipe design from MaxSpeed Motorsports for ~$1500 which is a few hundred more than their stock-looking design. They sound better than stock (in my opinion) and might add a few extra hp. Much cheaper than stock replacement and I'm willing to bet they will last much longer than a used set. There are quite a few options that are discussed here including Fabspeed and MaxSpeed. I installed them myself and posted an article on here about the experience.

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Thanks for the reply and I'm always open to ideas, so I appreciate the response. I have actually read your post you're referring to previously. In my personal situation, for what it's worth, I don't care too much about the sound (I have PSE) and the ~15 extra HP. Not saying there's no merit to that, but in my case I just don't value either of those too much.

One thing I've heard conflicting info on: Do you ever get CELs with the aftermarket cats (o2 sensor related, high flow cats, etc)? Are there any issues with emissions testing? I talked to Fabspeed and they swear no CELs and their X-pipe is just as good as OEM in every aspect. To be honest I personally really don't like the thought of going non-OEM.... but I also don't like the thought of $3200 on two cats either. I always think about the worst case and I can just see something happening later and Porsche telling me it's because I went non-OEM. I was also curious how much rigging had to be done to get those cats in to your 996. As I found out last weekend simply trying to get 4 O2 sensors replaced, there is not a lot of room back there in the exhaust. I have never worked on a car with everything packed so tight together -- it gave me a new found respect for the pros.

Interesting that you say the stock cats are known to go if you stress them on a track day. I know I don't have a Mezger turbo but this is supposed to be a "racecar". It seems ridiculous if the OEM cats can't take a nice flogging in a weekend at the track.

Edited by ferrugia
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Hey, I'm new to this forum. I bought a 2003 C4S with a blown IMS shaft and the PSE exhaust. I'm in the process of installing an LS3 motor and don't think I'm gonna need the Cats. I've got the original mufflers with less then 100mi on them also. I'm not sure which mufflers I'm going to use. The car is a southern (louisiana), one owner, 64k miles and no corrosion at all. Let me know if your interested and I'll send some pictures.

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Just to follow up on comment #9.

I have had the aftermarket cats on for almost a year without any significant issues. Definitely no CEL, although the engine seems to hesitate a little when it is first started and it is cold outside (ie <5 degrees celcius). I'm not sure it is caused by the cats though but I think I remember hearing other similar stories. My guess is that the backpressure has changed enough to cause the engine to not run perfectly when it is still in open-loop mode. It isn't a big problem and it just means revving the engine slightly higher than normal when it is very cold (but still below 3K) and it goes away after about 30 seconds.

I upgraded primarily to fix a rattling cat and I didn't want to put another 10 year old cat on to replace since the local options were asking ~$800 each. I also didn't want to spend as much on a single new OEM cat as it would cost to replace both with a better system.

I installed them myself on a Saturday morning. It took 3-4 hours of moving slowly, but it was a bit easier than I was expecting. The MaxSpeed cats had an adjustable clamp that compensates for any slight deviations in position, although they did fit perfectly. The O2 sensors fit without modification although one of the wires is now a little tight and didn't fit in the original mounting clamps.

The biggest challenge is getting the bolts off between the cat and the exhaust manifold without breaking them, but even if they break it isn't a huge problem. Spraying on a some releasing oil the night before (I forget the name but similar to WD40) solved that problem.

I actually have to get it emission tested in Ontario in the next few weeks but I'm anticipating an easy pass based on feedback from others with the same or similar cats.

Mine actually started rattling at the end of a 4 hour track day. Once I determined it was the cats I drove home and looked online and found a few other people who had run into the same problem. One of the comments was from someone who had replaced the cats with OEM multiple times and he tracked the car often but I don't really know if that was common.

My guess is that the cats are fine when new, but the added stress of the heating/cooling cycles when tracking the car shortens their life span. But that is just my guess.

The aftermarket ones (ie Fabspeed or NHP from MaxSpeed) are much higher quality than the OEM ones in terms of appearance, steel, and the welds but I have no idea how well the 200 cell cats stand up yet.

My $0.02 would be to replace with used in your case if you can find one for a reasonable price, and if not call up one of the reputable after-market companies.

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kgoertz, thanks for taking the time to follow-up. All very good info for me and for future reference for others I think.

The only other thing I would add about the person replacing the cats with OEM multiple times is that it makes me wonder if there was something else wrong with the car causing the cats to die. The originals on the car come with an 8yr/80K warranty, at least in my state. The dealer here told me they should be good for 100-150K miles on average as a rule of thumb.

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