Can a High Volume oil pump suck the floor up?

[fullmetaljacket]

If you have to cut it tight, for your own personal reasons, please don't go less than 3/8. If I understood what you said about no rebuilds.

OKAAAYY, so no less than 3/8" and no more than 1/2" off the floor? Gonna break past the witching hour on this one. it's the only time I've got.

 

[Curiousyellow71]

Heading to the grotto tonight to make my fitments and measurements. The new pick up will be at 1/4" to 3/8" off the floor.
As I mentioned before, my old pick up screen box was at 1/2" off the floor alone. The tube itself where its entry starts is at the top of that screen box and is another 1" higher. That meant that the tube entry was 1-1/2" above the floor. All together it would be fine if oil was always above the box and perhaps it was, but I don't want to take any chances.
I don't want to hurt this motor for a number of reasons, one being that I just don't have or can afford the time to break it down to rebuild and reinstall.
Pictures to follow.

Tube entry height is not relevant because it's air tight to the pickup assembly. Don't sweat that. Focus on the distance of the pickup to the bottom.
When we used to build pans we lengthened the pickup by taking two and welding them together. Much better then splicing in a chunk with two welds. That worked pretty good. Guessing you have a plan. All your stuff is very well thought out.Lol

 

[fullmetaljacket]

Tube entry height is not relevant because it's air tight to the pickup assembly. Don't sweat that. Focus on the distance of the pickup to the bottom.
When we used to build pans we lengthened the pickup by taking two and welding them together. Much better then splicing in a chunk with two welds. That worked pretty good. Guessing you have a plan. All your stuff is very well thought out.Lol

Yes, thank you. The car is surely a scientific experiment in motion.
I will post pictures when it’s dry installed and all.

 

[j-c-c-62]

The tube itself where its entry starts is at the top of that screen box and is another 1" higher. That meant that the tube entry was 1-1/2" above the floor. All together it would be fine if oil was always above the box

Understand that the first thing the oil pump will remove from the PU box is any trapped air inside, after that only oil, unless the outside the PU oil level ever drops to the level of the lower PU box opening to get or suck air, rather than oil. Until then, the PU box will ALWAYS be filled with oil.

 

[fullmetaljacket]

Understand that the first thing the oil pump will remove from the PU box is any trapped air inside, after that only oil, unless the outside the PU oil level ever drops to the level of the lower PU box opening to get or suck air, rather than oil. Until then, the PU box will ALWAYS be filled with oil.

Got it. I guess I wasn’t a good student of liquid hydraulic science back in the day. LOL. This stuff is as fascinating as it is confusing.
I think this thread in particular has clarified and taught many people out there about the inner workings of an oil system.

 

[BSB67]

When we used to build pans we lengthened the pickup by taking two and welding them together.

 

[dvw]

I run this same pick up opening 3/8" from the bottom. With a vacuum pump, using 5w25 oil. It has a crank scraper and a screen windage tray. Over 7000 rpm every pass. 1100 passes. One failure. Bent the bottom of the pan. Ran it 20 or so passes. Took it apart and repaired the pan. The screeen windage tray had shatered (another story). Couldn't get the material soon enough (dumb) so it ran without the tray. There was a line of sight between the pick up and the crank. 15 passes worth of wheelies w/o the tray. Spun a bearing. After this repair was when the scraper was added and the the screen windage tray went back in. Never another issue.
Doug

 

[fullmetaljacket]

Before installing everything dry tonight, here's a look into the aluminum pans sump trap door. (top photo)
The horizontal ledge splash baffles by the top don't extend outward as much as the ones on the steel pan, so it must be part of the oil flow plan. (bottom photo)

 

[fullmetaljacket]

In the belly of the least. Least as in few cubes. That's 493 inches right there. There's a lot of cleaning to do.

 

[Gunner1]

I would think the thicker oil would be more resistant to flow, therefore making it more willing to try and pull air in. Some builders have put plates on top of the sump to reduce vortex

It has always been my understanding that the shape and height requirements for the stock one was to reduce the tendency of a liquid to create a vortices hence the shape of the pickup disc. The depth setting was to keep it far enough away from the bottom of the pan as to allow a smooth controlled flow to the inlet pipe. The aftermarket pickup all seem to use the box and a higher setting. Even the high buck pumps we used on 454/427s that had the pickups as part of the pump body were square. My guess is that with the box and extra 1/8 inch it still has a smooth enough transition to provide a smooth flow to the pipe. I’ve built more bbchevs than I can count with a square box and 1/2 settings. It should be fine.

 

[fullmetaljacket]

It has always been my understanding that the shape and height requirements for the stock one was to reduce the tendency of a liquid to create a vortices hence the shape of the pickup disc. The depth setting was to keep it far enough away from the bottom of the pan as to allow a smooth controlled flow to the inlet pipe. The aftermarket pickup all seem to use the box and a higher setting. Even the high buck pumps we used on 454/427s that had the pickups as part of the pump body were square. My guess is that with the box and extra 1/8 inch it still has a smooth enough transition to provide a smooth flow to the pipe. I’ve built more bbchevs than I can count with a square box and 1/2 settings. It should be fine.

Thank you Gunner.
I've clarified and confirmed it to be good at 1/2"
Stef's pans (the fabricator of my pan) concurred as well.

I'm glad I didn't jump the gun in throwing my last assembler under the bus. I mean, he was assembling Ford pro-stock motors and all. It just got so confusing both with the Hoover plans using the stock oyster pick ups against the later aftermarket boxed pick ups.
With the oyster types, I can see why they would want them at 1/4" to 3/8". Even the original early '60's Max Wedge swinging pick ups are the oyster designs. Great design.

The boxed types are in their own galaxy.