Exhaust Manifold Flatness

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Cliffords
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Exhaust Manifold Flatness

Post by Cliffords »

Hi ,
My engine rebuild is near complete and I went to put the exhaust manifold back on this weekend . Its not very flat where is meets the head . As much as 1.7mm out on the centre two cylinders . Its a used one from one of the suppliers we all use . They don't have any other used ones to swap over . There does not seem to be any on e bay . My original one has big cracks in it albeit it is flat.

Has anyone put their one on a tool to even up the faces ? A linisher I guess or something similar . I am not sure we can weld the old one , unless you know differently ?

Thanks

Pete Boole
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Re: Exhaust Manifold Flatness

Post by Pete Boole »

Some years ago I set mine up in a jig on the milling machine and made minimal passes until flat. A local engineering company should be able to do the same. What is the downpipe flange like?

Pete

Marten
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Re: Exhaust Manifold Flatness

Post by Marten »

Cliffords wrote:
Tue Jan 10, 2023 09:59
Hi ,
My engine rebuild is near complete and I went to put the exhaust manifold back on this weekend . Its not very flat where is meets the head . As much as 1.7mm out on the centre two cylinders . Its a used one from one of the suppliers we all use . They don't have any other used ones to swap over . There does not seem to be any on e bay . My original one has big cracks in it albeit it is flat.

Has anyone put their one on a tool to even up the faces ? A linisher I guess or something similar . I am not sure we can weld the old one , unless you know differently ?

Thanks
Another approach is to use a big beltsander to get it back to flat. Good enough and no setup, so it should be cheaper than milling

Cliffords
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Re: Exhaust Manifold Flatness

Post by Cliffords »

Pete Boole wrote:
Tue Jan 10, 2023 11:06
Some years ago I set mine up in a jig on the milling machine and made minimal passes until flat. A local engineering company should be able to do the same. What is the downpipe flange like?

Pete
Hi, downpipe flange is good , it looks like it had some work done on it and new studs before it came to me . Its the block end that is a banana.
I am going to a couple of engineering places with it tomorrow , see what they say

David

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bash
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Re: Exhaust Manifold Flatness

Post by bash »

Good luck, my recent experiences with engineering companies found that they were all cnc and getting one to do it old school wasn't that easy.
Bash
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.

Marten
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Re: Exhaust Manifold Flatness

Post by Marten »

bash wrote:
Wed Jan 11, 2023 11:09
Good luck, my recent experiences with engineering companies found that they were all cnc and getting one to do it old school wasn't that easy.
Bash
I'd try to find an engine builder first

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