John,
You wrote:
"At start up with 20-50 oil the pressure is at 90lbs.
After 50 miles, at idle the pressure is maybe 15lbs acording to the
dash gauge. Idiot light never comes on. The engine shows no sign of
excess wear no unusual sounds, and the sparkplugs are clean."
You may not have any problem at all. My car has a TRF shortblock with
about 3000 miles on it. It has an oil cooler, electric fan, and rebuilt
head. My oil pressure after a good drive (30 miles or so) indicates
about 12.5 lbs. when idling at about 700 rpm and runs just over 50 when
driving. The owner's manual indicates the pressure should be 45 to 60
lbs at 2000 rpm and may drop to 25 lbs. in competion type use.
What is your pressure while your driving? What is it at 2000 rpm? Does
it go right up when you bring the engine off idle? What does your temp
gauge indicate? Mine runs at half when cruising and climbs to the second
to last mark when fully hot and idling at a stop light. This is with a
fresh change of Castrol 20W50, a Fram spin-on filter, and oil cooler.
I wonder what other people are seeing for idle oil pressure and
temperatures.
I hope these observations help alittle. I wouldn't be too quick to start
fixing a problem that may not exist.
Kerry
tr66pack@aol.com
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