I dunno. I was running 7-8psi at idle, 14-15psi at highway speed on
the 10W30 the PO sold it with, and 9-10psi at idle, 18-20psi highway
just by going to Mobil 1 15W50. Still not great, but it kept that
heart attack light from coming on all the time like it used to.

> Once an engine is up to operating temperature, I do not think the weight of
> the oil effects oil pressure as much as some people believe.