header flange
Thread Starter
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
header flange
I was just wondering, my header flanges have the raised circle lips around each hole like so many other I have seen. I have heard that filing these flat is a good idea.
Any word on this. I must not be searching the right words because I know I read about it here once.
Any word on this. I must not be searching the right words because I know I read about it here once.
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Theoretically in a perfect world with perfect mating surfaces and gaskets yes it would better flat but if the "circle lips" around the pipe openings is about the same on each one then it might help seal better because the "circle lips" will bite into the gasket. 
But if it ain't broke don't fix it, now if you have exhaust leaks that's different
But if it ain't broke don't fix it, now if you have exhaust leaks that's different
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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You *can* run a file across them to make sure the raised portions are flat, but DON'T remove the raised portions. You want them to embed into the gasket.
You might make sure there are no welds hanging down in the port that can obstruct flow.
JIM
You might make sure there are no welds hanging down in the port that can obstruct flow.
JIM
Thread Starter
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
I checked with a straight edge and all of the raised areas are the flat on each other so they stay in. Now I just need to determine if it is going to be worth it to cut each flange apart.
lots of people say yes, other say no. i really dont want to do this twice.
lots of people say yes, other say no. i really dont want to do this twice.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Ya know, I never really thought about it before, but header flanges are really the only mating surface that does that, aren't they? I mean, every other mating surface on the engine that I can think of has a flat surface and a flat surface bolted together with a gasket. Exept maybe the ones with o-rings. Can anyone explain this, or maybe point to an article that explains it?
Scott
