Exhaust driving me nuts

[SteinOnkel]

Hey party people,

So, I've been driving the Fiat more and more and the exhaust is absolutely atrocious.

1) The manifold leaks - oil. Yay to whoever designed the oil galley going into the stud. Let me ask you guys this: do you use copper sealant here? On the fasteners? Or also on the gasket?

2) The exhaust leaks like crazy where the stupid clamp is. I hate this clamp and this design (4-1 header), but I will be gosh darned if I have to source another overpriced header and downpipe. There has got to be a way to make this union seal up. I'm going to try a new clamp this time. Do you guys use sealant here or nah?

3) The downpipe hits various other components, which ties in nicely into 2). I currently have found two positions: First, doesn't hit much, but leaks like crazy at the manifold and two, hits everything but seals up decently at the manifold. What is your guys preferred method for bolting this together?

4) The flange gasket is currently out of stock at AR https://autoricambi.us/converter-flange-gasket-1974-80/
We all know AR doesn't make this stuff, so does anybody know of a more attainable, universal replacement part? How about Walker Exhaust 31312?

Thanks
An almost deaf Steiny

[Nut124]

Sorry about your troubles.

1) I put some black silicone inside the threads and on the stud threads before installing the studs. This was before I had oil in the engine.

[18Fiatsandcounting]

Ehh, what's that you say, Steiny? Speak up, lad!

1) I just use regular Permatex thread sealant, although maybe it was the high temp version. Seems to work fine. Clean the threads both in the head and on the bolt/stud before applying the sealant.

2) Both my spiders are 4-2-1 design, so I'm not much help here, but I have had other cars that had that sealing donut between the two pipes. The correct donut, the correct clamp, and the angle between the pipes, seem to be critical to getting a good seal.

3) Almost every aftermarket exhaust system that I have bought for a Fiat required taking it to a muffler shop after I was finished to get them to "fix" some of the things that were hitting or a bend angle that was wrong or whatever. Not sure why this is. That being said, I did buy an entirely new 2" system including two-into-one downpipe for my '71 from AR last year, and it fit almost perfectly. Only one minor issue with the rear hanger at the tailpipe, which reminds me, I need to fix that today.

4) That Walker exhaust gasket might work, and I would think any decent muffler shop could also get you what you need.

-Bryan