Catalytic converter air pipe

[Muststang]

I purchased the entire Pypes performance exhaust system. Headers, X-pipe, and catback system. I noticed on the high flow cats that they only come with 3/8 inch caps but no nipples to connect them to the air tubes. So I went to the hardware store and purchased a couple of black steel pipe nipples that are 3/8 inch as well only with slightly finer threads and I'm going to get a high temperature silicone hose and clamps to connect them to the air system.

The nipples are smooth all the way down to the threads and are originally intended for indoor plumbing so does it seem like a good idea to use them? Before I put them on I'll coat them in that ceramic paint that you bake for two hours at 400 degrees. My biggest worry is that they could leak around the threads.

What do you folks think?

 

[toyman]

I think you would be better off having the threads matched. I assume that stubs are 3/8" NPT. Is your concern with a leak about exhaust gasses or just the fact that it may leak from the fitting? If the pipe nipple is NPT they are a tapered thread and should seal well with with most sealants.

 

[revhead347]

I like smooth nipples. Any of you seen that boobie shot of Tera Reid? NASTY.

Kurt

 

[HISSIN50]

Is the pipe on the car already? If not, you could have an exhaust shop toss on whatever fitting you'd like.