<VV> oil pressure question

[Michael Kovacs]

 1966 140 pg very well rebuilt engine by me. Balanced, bored, Steadman heads, 
mild cam etc.  Clark .010-.010 crank run out almost .000 and plasti guaged 
carefully. 10,000 miles, runs very smoothly with strong acceleration. 20-23 MPG.

  Starts cold at 850 RPM at 35 PSI oil pressure. After a 20 mile drive with 
engine now at operating temp, Tach at about 2900 RPM = 60-65 mph, the oil 
pressure now has dropped to about 20 PSI. 


 It will stay there unless the engine is idled back to 750 RPM = 13-15 PSI and 
is still running smooth and no lifter clatter.

 Using fresh NAPA 10-40 oil. Clark filter. I forget if I did the oil pump, but 
probably looked it over and reinstalled. 


 I assume the pressure relief valve is the reason for the 35 PSI cold. The oil 
press  gage is electrical and I assume it is accurate due to the steady 35 PSI 
when cold even at cruising speeds. As oil heats, up just a steady decline in 
pressure.

 Suggestions? Should I check oil pump for clearence? Change filters? Check with 
mechanical gage too?

By the way I use the same NAPA oil in all four operating Corvairs and they hold 
about 35 PSi when hot. 




 MIKE KOVACS