LS1-450

iTrader: (33)

Found a 10 psi pressure drop during WOT (warm oil) even after the bladderless pre-oiler was filled. W/ pre-oiler on (oil open to pre-oiler) WOT pressure is 40 psi up to 5,700 RPM & w/ pre-oiler off (no oil entering pre-oiler) oil pressure is 50+ psi up to 5,700 RPM. Morale of the story is bladderless pre-oilers should be turned off while driving or use a bladder type pre-oiler w/ a pre-set oil pressure. Haven't tested a pre-oiler w/bladder, but would assume that because pressure can be pre-set against the bladder, there wouldn't be a pressure drop issue caused by a bladder type pre-oiler.

BTW, warm idle pressure went from 29-30 psi to 35 psi pre-oiler on/off.

I also feel like the oil cooling loop is causing a small pressure drop. Although, not enough to worry about or test.

Good news is that the pre-oiler pressure difference has never caused any engine problems, ie; no metal fines in the oil or filter.

DONAIMIAN

iTrader: (18)

Im curious as to what accumulator you used?

LS1-450

iTrader: (33)

I don't remember the exact brand name. It's a 1 qt. bladderless pre-oiler w/ an on/off solenoid. Originally, set up & tested w/ key on & also while engine is running & off when engine is turned off. Oil is sent to the oil gallery w/ key on before starting engine & pre-oiler is refilled while engine is operating.

It will now be set up w/ a separate switch where it can be turned off once it has been re-filled & before the car is driven, after starting.

It is not a Canton racing, Accusump, Amsoil, or other bladder type pre-oiler.