I guess I missed the start of the thread...
What kinds of problems do you get when the manifold is too thick or too thin?
And a follow up question... What is the torque specs on the manifold and carb
to the head?
And the third... do I use a sealent around the exhaust/carb gasket? I've heard
red RTV...
TIA
JB
1968 2L
In a message dated Sun, 3 Feb 2002 5:42:42 PM Eastern Standard Time, Marc
Sayer <marc@gracieland.org> writes:
> No! (Well okay, it might work for a few folks, for a while, but it is a bad
> "solution") You do not want to arbitrarily mess with the compressibility and
> compressed thickness of gaskets. In fact this is generally one of the worst
> cheap fixes for this problem. Gasket design is based on science and you can't
> really just mess with the gaskets like this most of the time. The proper
> solution for a bunch of reasons (including a tendency to warp the flange) is
>to
> buy headers made with the correct thickness flange. Any other solution
> (including gaskets, tabs welded onto the header flange, and stepped washers)
> will only lead to problems. You *might* be able to address a problem where the
> intake manifold flange was thinner with one of these approaches, as the intake
> manifold does not tend to warp, but with a header this is a major waste of
>time.
> Yes a car maker could perhaps design a stepped or two-part gasket that would
> work, maybe. But an individual does not have the resources to do the R&D for
> this, *and* the issue of header flange warpage is still unresolved with this
> approach. In order of preference the solutions to this problem are;
>
> 1-get a header with the right thickness flange
> 2-use stepped washers (because this way at least the header flange is the same
> thickness throughout)
> 3-weld tabs onto the flange (welding on the tabs will warp the flange and the
> flange must be surfaced *after* welding, plus the varied effective thickness
>of
> the flange will cause warpage problems)
> 4-use stepped gaskets (NOT recommended)
>
> Spray on Copper Coat or just plain silver hi-temp paint (the aluminum pigment
>in
> the paint acts as a gasket dressing) work well.
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