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deac

exhaust manifold

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I have a '40 Pontiac straight 8 and I pulled the manifolds off and now it's time to re-install them.  I have read a lot of good information on the Buick straight 8's but I have a Pontiac!  What I see on the manifold flanges(intake and exhaust) are flat circular areas on the manifolds at the stud mount area approximately an inch wide where a washer seats and the stud goes through.  When I took it apart there were flat, thick and inch wide washers there.  From my research from the Buick forums there are Bellville washers(aka: cup washers, spring washers) to be used at some point.  They are used to allow the manifold to move due to heat expansion.  

 

My first question is are those thick flat washers used first and then the Bellville and then the nut?

Second question is what is the torque spec for the manifolds and the sequence?  By my research the torque spec would be around 20 to 25 ft/lbs.

Third question is I have the manifold gaskets and is there a sealer or lubricant to go on the gasket?  I'm guessing due to the extreme heat and the expanding manifold a sealer would NOT work very well.  I like the solution of graphite powder and 50w oil mixture that one of the Buick guys use.

My fourth question is if those Bellville washers are used, and I am assuming they are, should I be putting them on all studs?

Edited by deac
mis-spelling (see edit history)

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only thick flat washers are used, tightening sequence is start at the center and work towards both ends, high temp copper spray or brush on gasket sealant.

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