Oil pressure vs. Viscosity

[Andrew Finney <afinney@tamsconsultants.com>]

Last week I asked the list why I had such low oil pressure in
my UrQ. That was with the Mobil 1 20W-50. Now it's cold and
I've moved to 10W-30. Why does my oil pressure go up
significantly? I used to have 2.5 bar gauge on the gauge, now I
get close to 4 bar gauge. Any thoughts? I thought it would go
the other way, given the extra resistance of the oil to
movement and shear. Cold oil has higher oil pressure than
warm oil, so why not thicker oil having higher pressure than
thin oil?

Andrew Finney
1983 UrQ.