I just got my 3" stainless system from Jason over at Enthuza. That whole process was probably one of the best from any vendor I've dealt with.

Anyway, the 3" cat is flanged (BEGi is reflanging my 1.6 DP for a 3" flange), but neither the BEGi kit nor the converter came with the 3" gaskets.

Jason indicated using red RTV on the mating surfaces in lieu of a gasket, but I have concerns about putting a silicone product that close to my wideband O2 sensor.

What would you do?

 

I've used gasket material on exhausts on evo's/sti's with no problems whatsoever.

I think the only time it craps out is when its near the turbo and super hot. Farther downstream I don't see why it wouldn't work.

But I am replacing my mani+turbo gasket so what do I know

 

I have been rocking no gasket between my dp/testpipe/catback and have no leaks. I would have no problem using RTV either tho. Ill probably do that next time i am under there.

 

sensor-safe high temp RTV

the end

 

Look around for Mr. Gasket #5960 exhaust gasket material. It's a 10"x10" piece of 1/16" fiber-impregnated-steel material which you can cut to size to make your own exhaust gasket.

Here's one source: Amazon.com: Mr. Gasket 5960 Ultra Seal Exhaust Gasket: Automotive

Here's a list of all of the various Mr. Gasket products in this range: Mr. Gasket :: Products

 

Per Jason's recommendations I used the red RTV. No problems whatsoever.

 

I always use copper RTV.

evidence:

 

this is exactly what I used and it fell apart between the mani/turbo.

 

Hmmm......the benefit to that would be I already HAVE a tube of copper RTV.

 

I'm liking this copper RTV idea. The gaskets on my car never want to sit properly and are always a pain in the *** to deal with. Especially the single o-ring gasket at the exhaust manifold, maybe I can get around that with some of this stuff.. I never realized they made an RTV that wouldn't ignite like a torch under exhaust heat.

 

you want the 300zx gasket from Vatozone. You will have to hollow it out, but the holes almost line up.

 

diy 1mm copper plate gaskets.. been using that for my wg for a while.. when the stock gaskets would blow out if a bolt got a bit loose, the copper one, lasts.. a long time..

 

I do the same, or use 1mm aluminum as well. For the bastards that don't want to seal, having one of the pipe bead makers ran near the inner diameter solved all my problems (basically raised the material a little bit and was crushed during tightening to take care of any imperfections).