Low oil pressure?

-
I'm not telling you to disagree, I trying to get you to see the big picture, the book is wrong and has been printed over and over and nobody changed it, so forget the book and look at the diagram. Your not a dumb guy but you refuse to acknowledge the book is wrong.

Take the filter off and put a U pipe there the oil still goes through the engine, take the plug out and plug the 2 holes going to the filter, the oil goes through the engine, pretty simple.

View attachment 1715207965
.
I won't Red X you however I don't agree with everything you're saying. LOL
I have a great idea for how to answer this question. That is at the Larry Shepherd seminar at the Nationals on Saturday someone asked him about leaving the plug out. And that should give us the answer we've all been waiting for.

Meet Butch Leal at the HDK Tent, signing autographs along with the debut of his 1975 B/MP Duster. Larry Shepard Tech Seminar - In celebration of the 50th Anniversary of the 340 Small Block debut in 1968, Larry has prepared some Tips & Tricks for the owner along with a Q&A. The Seminar takes place on Saturday at 1:00PM at the Nats Seminar/Match Box Race Tent located just behind the large Green Mopar Pavillion.
Unfortunately I won't be there so I can't ask him but surely someone here will be there and can do it.
 
Last edited:
I am not trying to be sarcastic here but a few years ago I overhauled my 47re in my Dodge Ram truck. On the valve body there is a valve called a boost valve. I have a full time oil pressure gauge on my trans. The line pressure runs about 90-100 lbs. when the torque converter locks up when that valve kicks in the pressure goes up to 130 lbs even though the line pressure is 90-100. I do not understand how that works.
Here is a good explanation I just found; apparently the boost valve is just a modifier to the pressure regulator valve's operation, used to boost pressure under certain conditions. (Hence the name....) But the pump's output is the source of the extra pressure; i.e., the pump is the 'active device' that supplies the pressure, higher or lower, and it is just being regulated to varying pressure levels. Not sure that answered your question.
Sonnax Dodge 48RE Hydraulic Features Revealed

Now if you want really freaky pressure rises, then consider the Powerstoke injection system, that has an internal oil pump that raises injection oil pressures to over 2000 psi. In that way, the electronic solenoid has to do very little work to activate the injector; the rest of the force is supplied by that highly pressurized oil. But again, there is an 'active device' used to raise the pressure; a special pump.
 
Here is a good explanation I just found; apparently the boost valve is just a modifier to the pressure regulator valve's operation, used to boost pressure under certain conditions. (Hence the name....) But the pump's output is the source of the extra pressure; i.e., the pump is the 'active device' that supplies the pressure, higher or lower, and it is just being regulated to varying pressure levels. Not sure that answered your question.
Sonnax Dodge 48RE Hydraulic Features Revealed

Now if you want really freaky pressure rises, then consider the Powerstoke injection system, that has an internal oil pump that raises injection oil pressures to over 2000 psi. In that way, the electronic solenoid has to do very little work to activate the injector; the rest of the force is supplied by that highly pressurized oil. But again, there is an 'active device' used to raise the pressure; a special pump.
I have read that Sonnax article before. It is very good but I could never follow the schematic. Smart guys over at sonnax.
Thanks for the explanation on the boost valve. I thought maybe the pressure rise was done with restrictions but your explanation makes sense.
 
Well... in a way, the pressure regulator IS a variable restriction...it can be in the main flow path, or as a 'shunt' off of the main flow path, but that depends on the load and application. But the pressure source ultimately has to be the pump. You can't have pressure in the system any higher than the pump's source pressure with zero output flow at the given pump speed, etc.
 
A friend of mine build a new home and had his water pipes plumbed in a circular loop from the water heater.
The idea was that even though no water faucets are open and using water, the water is able to continually flow through the water heater and around the house to keep hot water readily available.
This way when you opened the tap to get hot water there was not a long delay for the hot water to get to the faucet. The system is closed but it is looping under pressure.
Yep... but these systems employ a flow- or timer- activated pump for the recirculation.

Last time I checked... there is no pump in a Mopar oil filter LOL.
 
Yep... but these systems employ a flow- or timer- activated pump for the recirculation.

Last time I checked... there is no pump in a Mopar oil filter LOL.
Agreed. I was just trying to give explanation to the loop theory.
It's all good
 
Talked to Larry Shepard yesterday and asking the question of the effective of leaving the plug out. The first thing he said was
"You want that plug in there or you won't have oil pressure."
I ask what happens when the plug is left out?
His answer was that the oil coming up from the pump going through the two passages then hits head on at the end of the passage where it turns to go up into the motor.
I said so it's the two passages coming together causing turbulence that is causing this problem he says yes. He said but turbulence is not the word that I'm looking for and I can't think of it.
 
Well, that would be a valid reason, if only there was a significant amount of flow through the filter ports and filter with the plug out. But there isn’t. The filter is a restritor. There will be some turbulence, however.
 
"You want that plug in there or you won't have oil pressure."
I ask what happens when the plug is left out?
His answer was that the oil coming up from the pump going through the two passages then hits head on at the end of the passage where it turns to go up into the motor.
Help me understand this: The flow from the 2 passages hit 'head on' (even though they approach the joining point at right angles to each other) and somehow stop each other? That is what they would have to do if the result is "you won't have oil pressure."

But what happens to make the pressure at that point NOT force oil on into the main oil passage? There WILL be full, no-flow pump output pressure at that point if there is no net oil flow.

At best, you can only claim that some turbulence occurs, but turbulence is a feature of flow.... so if you claim turbulence, then that means that there IS flow and so pressure into the engine can't be zero.

The pressure at that joining point will become a certain amount below pump pressure output and is going to be dominated by the relatively smaller pressure drop in the direct passage. If you could measure flow resistance through that direct passage (R1), and through the filter and its passages (R2), then then resulting overall flow resistance would be approximately R1*R2/(R1+R2). (This is the standard first-order resistance formula for 2 parallel paths, and applies to heat flow, electric circuits, and simple fluid flow.) Any added resistance due to turbulence would be added to that overall filter+ passage flow resistance. But to stop flow and have zero engine pressure, the turbulent resistance would have to be infinite, and since you can't have turbulence without flow, that can't happen.

I'm just trying to explain why the flow and pressure won't be zero.
 
I told you he's not his father!
If this is the Larry Shepherd from Akron, it looks like he is not even related to the other Larry Shepherd(s). Too many Larry Shpeherds....and I wonder of they are related to Doug Shepherd, who did work for the DC program IIRC.
 
Help me understand this: The flow from the 2 passages hit 'head on' (even though they approach the joining point at right angles to each other) and somehow stop each other? That is what they would have to do if the result is "you won't have oil pressure."

But what happens to make the pressure at that point NOT force oil on into the main oil passage? There WILL be full, no-flow pump output pressure at that point if there is no net oil flow.

At best, you can only claim that some turbulence occurs, but turbulence is a feature of flow.... so if you claim turbulence, then that means that there IS flow and so pressure into the engine can't be zero.

The pressure at that joining point will become a certain amount below pump pressure output and is going to be dominated by the relatively smaller pressure drop in the direct passage. If you could measure flow resistance through that direct passage (R1), and through the filter and its passages (R2), then then resulting overall flow resistance would be approximately R1*R2/(R1+R2). (This is the standard first-order resistance formula for 2 parallel paths, and applies to heat flow, electric circuits, and simple fluid flow.) Any added resistance due to turbulence would be added to that overall filter+ passage flow resistance. But to stop flow and have zero engine pressure, the turbulent resistance would have to be infinite, and since you can't have turbulence without flow, that can't happen.

I'm just trying to explain why the flow and pressure won't be zero.
.
I didn't say he was right and I didn't say I believed what he told me.
 
If this is the Larry Shepherd from Akron, it looks like he is not even related to the other Larry Shepherd(s). Too many Larry Shpeherds....and I wonder of they are related to Doug Shepherd, who did work for the DC program IIRC.
.
I would assume it was the correct Larry Shepard since this is the guy that's giving the seminar at the Mopar Nationals on Saturday.
 
Help me understand this: The flow from the 2 passages hit 'head on' (even though they approach the joining point at right angles to each other) and somehow stop each other? That is what they would have to do if the result is "you won't have oil pressure."

But what happens to make the pressure at that point NOT force oil on into the main oil passage? There WILL be full, no-flow pump output pressure at that point if there is no net oil flow.

At best, you can only claim that some turbulence occurs, but turbulence is a feature of flow.... so if you claim turbulence, then that means that there IS flow and so pressure into the engine can't be zero.

The pressure at that joining point will become a certain amount below pump pressure output and is going to be dominated by the relatively smaller pressure drop in the direct passage. If you could measure flow resistance through that direct passage (R1), and through the filter and its passages (R2), then then resulting overall flow resistance would be approximately R1*R2/(R1+R2). (This is the standard first-order resistance formula for 2 parallel paths, and applies to heat flow, electric circuits, and simple fluid flow.) Any added resistance due to turbulence would be added to that overall filter+ passage flow resistance. But to stop flow and have zero engine pressure, the turbulent resistance would have to be infinite, and since you can't have turbulence without flow, that can't happen.

I'm just trying to explain why the flow and pressure won't be zero.
The books I have say the pressure would be low and erratic not necessarily none.
I know that my x block and the r race blocks have a feature cast in to reverse feed the main oil galley. The idea there was opposing pressures cancel each other to stop velocity in the galley to better feed the main bearings. That could partially be what happens without the plug. As I have said, without the plug there is not always a clearly defined flow path which for lack of a better word could cause erratic flow.
 
The books I have say the pressure would be low and erratic not necessarily none.
I know that my x block and the r race blocks have a feature cast in to reverse feed the main oil galley. The idea there was opposing pressures cancel each other to stop velocity in the galley to better feed the main bearings. That could partially be what happens without the plug. As I have said, without the plug there is not always a clearly defined flow path which for lack of a better word could cause erratic flow.


You need to stop the flow from the other direction if you bring the flow in from the front.

And BTW, that won't fix one single oiling issue. I've posted so much on here about that topic that I ain't doing it again. The oiling issue isn't about where the oil comes from, oil velocity, crossover tubes or any of that other bullshit.

A 1960's SBC will oil itself to 10,000 RPM's plus and not have bearing issues. If you want the truth, study a SBC and then figure out how to copy that.

Anything else s either bullshit or lies.
 
The books I have say the pressure would be low and erratic not necessarily none.
I know that my x block and the r race blocks have a feature cast in to reverse feed the main oil galley. The idea there was opposing pressures cancel each other to stop velocity in the galley to better feed the main bearings. That could partially be what happens without the plug. As I have said, without the plug there is not always a clearly defined flow path which for lack of a better word could cause erratic flow.
Actually the way it works is that the flow is roughly half from either end versus a standard block, so the velocity is lower in the back of the main gallery, where there have been ideas/reports that the higher velocity makes it easier for the oil to 'shoot by' main #4. But the pressures don't 'cancel'; the pressures would be high on each and lower in the middle, and higher in the middle than with the stock feed, and the average pressure is higher throughout (assuming the split and plumbing to each end is good). The stock setup has pressures dropping from back to front, with the center and front pressures being lower than with the dual feed, because the full flow has to pass through the back half of the gallery.
 
Actually the way it works is that the flow is roughly half from either end versus a standard block, so the velocity is lower in the back of the main gallery, where there have been ideas/reports that the higher velocity makes it easier for the oil to 'shoot by' main #4. But the pressures don't 'cancel'; the pressures would be high on each and lower in the middle, and higher in the middle than with the stock feed, and the average pressure is higher throughout (assuming the split and plumbing to each end is good). The stock setup has pressures dropping from back to front, with the center and front pressures being lower than with the dual feed, because the full flow has to pass through the back half of the gallery.


And none of this ^^^^^^^^ makes a pinch of **** difference if you don't correct the oil timing. Fix the oil timing and you can turn a SBC 10,000 RPM's and it will not eat a bearing.

Mentally masturbating over theory that has been wrong since day 1 won't make it work.


Fix the oil timing.
 
You need to stop the flow from the other direction if you bring the flow in from the front.

And BTW, that won't fix one single oiling issue. I've posted so much on here about that topic that I ain't doing it again. The oiling issue isn't about where the oil comes from, oil velocity, crossover tubes or any of that other bullshit.

A 1960's SBC will oil itself to 10,000 RPM's plus and not have bearing issues. If you want the truth, study a SBC and then figure out how to copy that.

Anything else s either bullshit or lies.
I know we have had that discussion before.
As I have posted before I am copying that mod from a very successful
Small block racer Charles Sanborn rest in peace. He looped a line around to the front.i have a good friend with an 8 second Daytona big block who has his main galley looped as well but from front to back.
Some things people are just gonna disagree on.
Sanborn brought the main oil line out of the block to a multi port filter block that divided it and sent it back to the rear inlet and the front inlet. If I recall you are referring to the timing issue.
I believe that issue has merit but I also believe that some blocks with a counter bore in the main saddles would adjust that. My 69 340 block never had those counter bores. My x block does.I suppose there will always be differing views on certain things.
 
I know we have had that discussion before.
As I have posted before I am copying that mod from a very successful
Small block racer Charles Sanborn rest in peace. He looped a line around to the front.i have a good friend with an 8 second Daytona big block who has his main galley looped as well but from front to back.
Some things people are just gonna disagree on.
Sanborn brought the main oil line out of the block to a multi port filter block that divided it and sent it back to the rear inlet and the front inlet. If I recall you are referring to the timing issue.
I believe that issue has merit but I also believe that some blocks with a counter bore in the main saddles would adjust that. My 69 340 block never had those counter bores. My x block does.I suppose there will always be differing views on certain things.



Sanborn was wrong then, and is wrong now. I to,d him way back when I was on mofartcrap.

If you can't understand the simple physics that have been worked out for decades, I can't help you. You can move the oil supply anywhere you want and it won't make a pinch of **** difference.

It isn't a supply issue. It isn't an oil velocity issue. It's an oil timing issue. You can argue the point all you want, and you will still be wrong.

I've been there. I've done that. I've made over 2 hp/CID at 8500 and the stock system is plenty. If you correct the oil timing. All that other **** is a waste of time and money.

Sanborn was wrong. I sent him several emails with pictures. And he always said my way works. But he never turned the RPM I did.

Fix your oil timing. Don't **** with that other stuff. It's stupid. If you would have looked at a SBC block and crank like I said, you'd see how far off the timing is.
 
What timing are you talking about YR rod feed timing
I've had customers who had me drill the front of SBC for front end feed- mostly sprinters and road/ circle track I have/ had a jig for it
I've fed the mains from the side where the bearing halves join
I've put the pressure relief at the opposite end of the block from the pump
lots of things
good points
 
-
Back
Top