> In addition to Randall supporting my LBC mechanic as to my state of mind
> Just how is the pressure bypass valve supposed to be set in a normal
> situation?
In a "normal" situation, you never mess with it. That's why there's no
procedure in the book.
However, the factory specification is for warm cruise oil pressure to be
approximately 70 psi. Since the valve is not perfect, I'd say your 80 psi
indicated is plenty close enough. Since your engine is nice and tight, the
valve is flowing a lot of oil, and it's normal for the pressure to rise somewhat
at higher flows.
There's also the issue that the factory gauge is unlikely to be accurate to
within 10 psi ... IMO if it is that accurate, it's purely a coincidence. The
reading on mine will literally vary that much just depending on how I tighten
the nut on the oil line !
So if you do want to adjust the valve, then I'd suggest starting with a known
accurate pressure gauge. You could then adjust the valve to give you exactly 70
psi at warm cruise. (And likely have to turn it back up again when the engine
wears in a bit.) To adjust the valve, you loosen the locknut (the smaller of
the two 'nuts') then turn the slotted screw in to raise the pressure, out to
lower it. Don't forget to tighten the locknut afterwards.
Randall
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