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YOUR RESEARCH1999 C2 with dreaded rattle from rear end...take off cats best bet?
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Use cats unless you can buy a matching pair
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I'd be wary of used cats unless you can buy a matching pair.
1999 C2 with dreaded rattle from rear end...take off cats best bet?
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Leading evidence: 'Use cats unless you can buy a matching pair' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use cats unless you can buy a matching pair' (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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My info is even used OEM/OE converters are no longer legal.
1999 C2 with dreaded rattle from rear end...take off cats best bet?
Use oem cats
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1999 C2 with dreaded rattle from rear end...take off cats best bet?
Use rennlist
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1999 C2 with dreaded rattle from rear end...take off cats best bet?
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Anyone know of any? Have a pair?
Alternatives?
In California so aftermarket options a little limited and I've heard too many stories about throwing CEL...
Suggestions / pointers / leads on a pair of OEM catalytic converters or alternatives appreciated!
(Yeah I've read past threads; looking for current thoughts or leads)
Keep the engine and exhaust system stock. If you have to take your car to a dealer you stand a good chance of them not working on it if they find non-Porsche or Porsche approved parts.
^^^ Why would anyone take a '99 to a dealer for servicing???
The reason to stay OEM is so that passing smog isn't a big hassle.
There really aren't any legal alternatives than OEM.
I'd be wary of used cats unless you can buy a matching pair. One of my cats failed after a track day resulting in a rattle and my guess is the other one isn't far off. I read (on here) that it isn't unusual for the stock cats to fail when tracking the car. I haven't tried to sell my 'good' cat since my guess is that it probably doesn't have much life left in it.
If I were in California I would probably take the rebuild route. There was a discussion on rennlist about a company that was rebuilding the 996 cats that might be worth digging up.
I also developed the dreaded rattle recently at a track day. I ended up going with the Speedtech X-pipe 200 cell sport cats. I really like the sound (GT3 like) and there is a noticeable increase in power above 4k RPM. The torque band has moved up the rev range a bit due to the reduced back pressure. I have them paired with FabSpeed MaxFlow exhaust and FabSpeed CF competition intake. Not loud below 4k and then it starts sound like a screaming banshee. I'm sure I could benefit from an ECU tune to maximize the performance of the mods. Including installation, it was over $2k less than going with factory cats. Sent from my iPad using Rennlist
My info is even used OEM/OE converters are no longer legal. This subject came up a while back when I bought a pair of converters for my Boxster from a salvage yard. One of the original ones had a horrific rattle from a loose brick and I finally got tired of the racket and the occasional CEL with an underperforming converter error code popping up. The used converters work just fine and the occasional CEL with an underperforming error code no longer pops up. The converters I bought used cost less than half the cost of factory new ones.
If you can find this tread in it I pasted some links to a web site that listed CARB certified converters. I know nothing about their cost, how well they fit, and so on.
Added: I found the thread, but the link I posted no longer works.
Here's the link to the thread:
https://rennlist.com/forums/996-foru...t-options.html
This is a source reference. Confirm exact model applicability in the original material.
