Larry, et al,
Hmm, I think thing need to be put into perspective here. Most
engines have separate "cam bearings" (sleeves) installed into the block
for the cam to spin within. Some don't. The Spridget 1500CC engine is
a case in point; its cam spins within machined bores in the block. If
the cam bores in the block get worn out of tolerance, the oil pressure
could indeed suffer. Also, if the bores wear too much, the cam will
flex under the valve spring pressure. The cam can break because of
this, but the most frequent sign of this is that the valve lash won't be
constant. I had a Fiat 128 Spyder DOHC engine that manifested worn cam
bores in this way. The fix is, reputedly, to bore out the cam bores for
bearings and run an XXX cam. Take your pick; I've been told of several
different to use.
My thought is that I'd have to see signs of real probs in the cam
bearing area before I'd bother. By signs, I mean a real good going-over
of the cam bearing journals on the cam for signs of loss of alignment,
out-of-round, etc.
Hope this clears it up a bit,
CR
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