exhaust manifold sealer

[70CitrusZ]

Imagine my surprise when I called a GM parts dept. asking for exhaust manifold gaskets and they said there was no such part from GM. They never used gaskets from new, so why would you need them now, unless the manifold surfaces are poor or warped.....I still use gaskets.

[k92]

Thanks for the responses. The exhaust ports on the heads were already milled,but nothing has been done to the manifolds yet.They are currently at Mcneish's getting refinished and I dont know if getting them cut would somehow damage the coating on them. I'll probably try the copper sealant just in case, hate those pesky exhaust leaks!!

[nuch_ss396]

Contact Jerry M and ask him to put a straight edge across
the flange surfaces. If they are problematic, ask Jerry
to get them fly cut.

Steve, I can't imagine why it cost you that much money to
get the 455 manifolds cut. It's a flat surface and somewhat
easy to indicate for flatness. Then, you just take a light
cut for cleanup. Unless I'm missing something, a skim cut
should be fairly easy to do. I will have that done to my
manifolds before I install them. 30+ years have to account
for a little warping I would expect.

Steve

[L78steve]

Once the jig is fabricated it is simple.But the manifolds have to be firmly held or chatter will occur.This will ruin the cutters and the manifolds.

[elcamino72]

I agree, have Jerry check them. I've gotten them machined in the past at a local shop and I forget what they charged me, but it wasn't much. Now I just trim the gaskets and you really don't see them however on a 1000pt car I would certainly not use gaskets.

[nuch_ss396]

Sounds like the perfect application for a surface grinder,
not a fly cutting operation.

[Charley Lillard]

or a table type belt sander.

[L78steve]

The problem I found with a belt sander is the belt lap joint,every time it comes around it rounds the leading edge of what ever your cutting.