A few weeks ago I started to hear the distinctive tick-tick-tick of an exhaust leak reflecting off cars next to me, sounded like it was coming from the passenger side up front. I have JBA shorty headers and cat pipes on the car; the driver side one has a v-band between the header and cat pipe, but the passenger side is just a 2-bolt flange. I figured that was the source of the leak, so I picked up a new gasket and got the car up on a lift. When I pulled the passenger side cat pipe to replace the gasket, I found that not only the upper gasket (header-to-cat pipe) was bad, but the catalytic converter seal (donut gasket between the cat pipe and the cat-back exhaust) was also in really bad shape. Unfortunately, I hadn't thought ahead to get that seal, too, so I had to put it back together as-is.
I did a little homework and found the OEM part is #12555555. List on those is a bit over $28, and you can find them on Ebay for ~$22. But a couple folks on ls1tech mentioned that Trubendz makes a replacement seal, too, which is more affordable than the OEM part and seems to be better made. They were using them with Trubendz cat pipes, but from what they could tell, they should work with the OEM cat pipes, too. One of the guys on ls1tech, isis, sent me some pics of his, and based on those pics I was pretty much certain they would work for me, too. So, I contacted Josh @ Trubendz to see what the story was. He couldn't definitively say they would work for me - again, they're designed to work with their own cat pipes - but I bought a pair - $15 each, + $5 shipping.
My exhaust is a bit of a hodge-podge of parts, but I specifically set it up so I could put stock parts back in place if I ever needed to. So, while the headers and cat pipes are from JBA, I had an exhaust shop cut the downstream flanges off some stock cat pipes and weld them onto the JBA pipes. The cat-back is a Corsa setup, which of course is designed to bolt up to a stock set of headers/cat pipes. For the purposes of catalytic converter seal replacement, it's equivalent to a stock setup.
Here are the pics that isis sent me:
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The parts came in last week and I put the car back up on the lift Friday and installed them. You can see how badly my stock ones were eroded:
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(The orange residue is some Ultra Copper RTV that I slathered on the passenger side one when I initially discovered the problem and didn't have a new seal to fix it.)
And proof that the Trubendz parts fit perfectly:
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Note that they're actually 2 pieces - the sleeve, and then the donut gasket itself. The stock ones are also two pieces, and depending on how they've rusted themselves together over the years, you may find the sleeves are stuck to the cat pipe, or you may find that the whole thing (sleeve and donut) comes out as one piece just fine. (Mine came out in one piece, no problems.) I suppose if your original sleeves were rusted to the cat pipes and didn't want to come out you could just slip the new donut gasket material onto the sleeve and call it good.
I sent all of the above pics to Josh and he said they would probably add the seals to their website as an individual listing when they do the next revision to the site. In the meantime, if you've got leaky gaskets, you can call Josh up and ask for the gaskets.
I did a little homework and found the OEM part is #12555555. List on those is a bit over $28, and you can find them on Ebay for ~$22. But a couple folks on ls1tech mentioned that Trubendz makes a replacement seal, too, which is more affordable than the OEM part and seems to be better made. They were using them with Trubendz cat pipes, but from what they could tell, they should work with the OEM cat pipes, too. One of the guys on ls1tech, isis, sent me some pics of his, and based on those pics I was pretty much certain they would work for me, too. So, I contacted Josh @ Trubendz to see what the story was. He couldn't definitively say they would work for me - again, they're designed to work with their own cat pipes - but I bought a pair - $15 each, + $5 shipping.
My exhaust is a bit of a hodge-podge of parts, but I specifically set it up so I could put stock parts back in place if I ever needed to. So, while the headers and cat pipes are from JBA, I had an exhaust shop cut the downstream flanges off some stock cat pipes and weld them onto the JBA pipes. The cat-back is a Corsa setup, which of course is designed to bolt up to a stock set of headers/cat pipes. For the purposes of catalytic converter seal replacement, it's equivalent to a stock setup.
Here are the pics that isis sent me:
The parts came in last week and I put the car back up on the lift Friday and installed them. You can see how badly my stock ones were eroded:
(The orange residue is some Ultra Copper RTV that I slathered on the passenger side one when I initially discovered the problem and didn't have a new seal to fix it.)
And proof that the Trubendz parts fit perfectly:
Note that they're actually 2 pieces - the sleeve, and then the donut gasket itself. The stock ones are also two pieces, and depending on how they've rusted themselves together over the years, you may find the sleeves are stuck to the cat pipe, or you may find that the whole thing (sleeve and donut) comes out as one piece just fine. (Mine came out in one piece, no problems.) I suppose if your original sleeves were rusted to the cat pipes and didn't want to come out you could just slip the new donut gasket material onto the sleeve and call it good.
I sent all of the above pics to Josh and he said they would probably add the seals to their website as an individual listing when they do the next revision to the site. In the meantime, if you've got leaky gaskets, you can call Josh up and ask for the gaskets.
