Don Terrill’s Speed-Talk

I have a 8 1/4" Moroso pan, on hard braking the oil pressure drops. How much oil should I put in when changing the oil and filter. I have been using 6 Qts. Oldhead

And what the heck engine are we talking about here?
What Moroso model pan?

I would work the other way and add in 2 more Qts then drop out 1/2 Qt at a time until the hard brake pressure drop shows back up.

Might need a baffle to keep oil near the pickup. Had this happen on a pan I designed for the stroked 2.3 to 2.5 ranger engine. Worked fine until they installed it on the actual next years model with anti lock brakes were added.

Most of those pans were 8 quarts plus the filter.

It would be nice to know what engine and part number of oil pan you are working with.

If the windage tray is bolted to the pan as mine is, it should have the windage tray extend into the sump area above the oil pump. I have seen pics of some Moroso windage trays that did not do that.This keeps the oil in the sump during deceleration in my opinion....

if the pan has swinging trap doors do not install the pan with the engine upside down as some trap doors can get stuck in the open position.

I have used it for 20 years and just noticed the problem since installing Comp. Cams Elite roller lifters. It looks like Moroso #20180, 8 1/4 deep, it has a swing door. I also use the GM baffle Oldhead PS: Thinking back 20 years, it might have said 6 quarts, But is that plus 1 for the filter??

Normal condition for a wet sump oiling system. Most just don’t notice it. Only fix is an accumulator. Special pans, baffles, etc won’t work. Best fix is a dry sump but not needed on most builds.

oldhead wrote: ↑Mon Oct 23, 2017 2:03 pm I have used it for 20 years and just noticed the problem since installing Comp. Cams Elite roller lifters. It looks like Moroso #20180, 8 1/4 deep, it has a swing door. I also use the GM baffle Oldhead PS: Thinking back 20 years, it might have said 6 quarts, But is that plus 1 for the filter??

I check these pans by setting them level on the bench and 1 quart at a time I filled it with either water or kerosene till it reached to the bottom on the windage tray. added 1 quart for the filter and 1/2 quart for the oil passages in the engine.

filter holds a quart and there's has to be a quart in transition.
That leaves 4 in the pan at most.

Coloradoracer wrote: ↑Mon Oct 23, 2017 3:29 pm Normal condition for a wet sump oiling system. Most just don’t notice it. Only fix is an accumulator. Special pans, baffles, etc won’t work. Best fix is a dry sump but not needed on most builds.

X2...the faster you go the faster you need to stop! Mine would do that every pass and recover soon as I turned to the return road.never had any issues because of it but dry sump cured that.

oldhead wrote: ↑Mon Oct 23, 2017 2:03 pm I have used it for 20 years and just noticed the problem since installing Comp. Cams Elite roller lifters. It looks like Moroso #20180, 8 1/4 deep, it has a swing door. I also use the GM baffle Oldhead PS: Thinking back 20 years, it might have said 6 quarts, But is that plus 1 for the filter??

If since installing the different lifters AND if you are still doing everything else the same it is probably more oil going past your new lifters than was with the old lifters. Therefore more oil on its way to the pan and less actually IN the pan. If this is the case, simply adding some extra oil will likely get your running pan level back to where it was prior to the new lifters.
Ideally though, oil pan/system rework would be a better solution OR as suggested just fit an accumulator to cover the times when this happens.

oldhead wrote: ↑Mon Oct 23, 2017 2:03 pm I have used it for 20 years and just noticed the problem since installing Comp. Cams Elite roller lifters. It looks like Moroso #20180, 8 1/4 deep, it has a swing door. I also use the GM baffle Oldhead PS: Thinking back 20 years, it might have said 6 quarts, But is that plus 1 for the filter??

What's the new lifter to bore clearance compared to the previous set?
Have you noticed a hot oil pressure change/drop?
Me thinking these are a tad smaller and you're pumping more oil around and leaving less in the pan.

when chevy came out with the BBC they switched to piddle valve lifters. at the drag strip you needed to run a quart over full to prevent a oil pressure drop because the piddle valve lifers allowed more oil to be trapped upstairs. we just changed the lifters to edge orifice type to stop the problem.

oldhead wrote: ↑Mon Oct 23, 2017 2:03 pm I have used it for 20 years and just noticed the problem since installing Comp. Cams Elite roller lifters. It looks like Moroso #20180, 8 1/4 deep, it has a swing door. I also use the GM baffle Oldhead PS: Thinking back 20 years, it might have said 6 quarts, But is that plus 1 for the filter??

6 quarts in the pan itself. Add oil for the filter.