Intake Manifold Question

[RLSIDWELL]

Am getting ready to replace intake manifold gasket and, since I have everything apart, was wondering if someone can tell me how to determine if I need to have my intake planed to match the heads - FE 390.

As always, any input is always appreciated.

[*13*]

If you are concerned about warpage I would put a straight edge on the mating surfaces to check them first. Other than that I would pull the old gaskets & visually inspect them for anything other than a flat smooth surface. What makes you think there is a problem?

[RLSIDWELL]

The manifold seems to me to fit right. When I took it off, I can see the indentations on the gaskets around the ports like it is torqueing down correctly. I thought I read a post once that talked about checking the fit to ensure it is correct yet I am unable to find it again. Maybe I dreamed it! Anyway, since I had it apart I thought it would be a good time to double check. Straight edge confirms it is straight. Thanks for the reply.

Rick

[afret]

One more thing to check is the angle of the intake face of the manifold. I bought a precision protractor like this one:
http://www.use-enco.com/CGI/INSRIT?P...&PARTPG=INLMK3
and checked the angle of the intake surface of the head to the end rail of the block to make sure it is 45* and checked the angle on the intake manifold. I checked my Blue Thunder, Streetmaster, Victor, PI, and Street Dominator intakes. The Blue Thunder and Victor intakes were a bit off by about 10 minutes which I guess is about 1/6 of a degree. They both had a decent imprint on the gaskets but still allowed some oil to get into the ports. Not enough to cause smoking but there would be some oil on the spark plug threads and in the ports. The Streetmaster was off by about 1/2 degree. I had a machine shop mill the intake to correct the angle problem on the Victor. I have the Victor on my engine now and it is sealing very well. Another way to check if the head and intake manifold angles match is to place the intake on the heads without a gasket. You can check the gap where the intake meets the head and make sure it sits parallel without the gap getting larger from top to bottom and vice versa. It's amazing how common machining errors seem to be on these intakes.

[Michael C Henry]

The top rail that the valve cover seals against should match. My heads were shaved and the rails didn't match . I ended up having the manifold shaved to match .Gasket lines up and matches ports manifold and head so it must have been mismatched before. Bolts were easier to install. Area for the gasket accross the front and rear of the block allmost dissappeared . I ended up using blue oilresistant RTV. Watch the corners where the manifold gaskets and front and rear of blok meet . Notorious leakers.