David Reher doesn't agree with us:

Quote
Unfortunately, too much vacuum can be a bad thing with a wet-sump pan. Remember that it is the pressure in the pan that forces oil into the pickup. When you reduce the pressure in the crankcase with a vacuum pump, you also reduce the pressure differential between the inlet side of the pump and the pan. Normal atmospheric pressure is approximately 30 inches of mercury; if you reduce the pressure in the pan to 15 inches, you have only half as much pressure pushing the oil into the pickup.


Article from National Dragster

I can see that positive sump pressure helps the oil pickup and less than atmospheric pressure would fight it - but maybe the combination of sump vacuum and the dry oil cooler was an issue. I don't like the fact that there's no anti-drainback valve in the OE oil cooler.

Frank

'89 [color:"white"]G-Raider[color:"white"] [color:"black"]Supercharged 3.0L, MegaSquirt 2, lockup A/T, 2.5" exhaust, 172k, Cibie H4s/Oscar SCs, Hella Micro DE fogs, Cobra CB, Superwinch hubs, LSD rear/Aussie Locker front, Bilsteins, Lifeline AGM, Rust-Oleum