Maybe you guys can answer this for me. I am cleaning up my exhaust and
intake manifolds prior to reassembling after blowing out the exhaust
gasket. It's been a long process--nearly every bolt either chiseled off
or drilled out. I mounted the intake on top of the exhaust and found
that the flange faces are not in the same plane. The manual calls for a
max of .010" warpage between faces of the same manifold, but no spec is
given when they are assembled. The cylinder head flanges are in the
same plane. I can take this to work and mill the manifolds while they
are assembled, but I wanted to ask if anyone knows if there might be a
reason if they are made this way intentionally (thermal expansion,
maybe?) before I cut them. Also, should I spotface the back side of
the flanges to equal thickness after milling, or does this matter--I am
thinking of equal clamping pressures. Any ideas before I fire up the
Bridgeport? BTW, the intake flange faces extend past the exhaust flange
faces by approx. 1/32". This makes sense to me if the exhaust manifold
has been surfaced by itself to correct prior warpage. Doesn't seem to
me that this can possibly seal correctly the way it is. Any ideas?
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