Hey Art:
When I got my SPF the
oil pressure was very low, all the time. I removed the 20W-50 Castrol and the Fram filter. I installed a Mobil1 filter and 5W-30 Mobil1
oil. The pressure went up! That's right, it went up. At 2,000 RPM I run about 55 PSI (hot), 40 at idle(hot).
I figure the thicker
oil had a hard time going through the cooler and all the plumbing involved. Remember the pressure pick-up is after all the tubing and cooler. I won't get into Reynolds Number and turbulent versus laminar fluid flow, but you can be sure it has a lot to do with the loss of pressure.
Just for the record, Mobil1 comes in 0W-20, 0W-30, 0W-40, 5W-30, 10W-30 and 15W-50. It does not come in 10W-50 or 20W-50. The Fram filters are not the best, go with the K&N or Mobil1 filter.
Give me a call, I'd love to see the car.
Bob