hard or soft copper line for a valley oil gallery bypass line?

[Rapid Robert]

the utube vid that described it said to use a hard copper (I forget the letter designation) but a utube pro plumber said to use soft copper (in his demo) because you would be flaring it. what do you guys think? thank you for your time. RR

 

[Demonic]

It needs a couple of shallow bends iirc, hard to do with hard pipe, and the soft copper is a bit less prone to cracks over time. Soft for sure.

 

[Newbomb Turk]

the utube vid that described it said to use a hard copper (I forget the letter designation) but a utube pro plumber said to use soft copper (in his demo) because you would be flaring it. what do you guys think? thank you for your time. RR

My question is why are you running a cross over tube? If you are running it because you have blocked all the oil off to the drivers side lifter bank, than that’s a reason to do it.

If you haven’t blocked off the oil to the drivers side lifter bank there is no reason to bother with it.

Because Chrysler (or Chrysler people) put out bad information on what that tube is for.

 

[Rapid Robert]

it is a 3/8 copper tube from the pass oiling gallery over to the drivers side oiling gallery then the passenger side front oil gallery feed down to the #1 main is blocked & the #1 main is fed from the drivers side gallery. this slow down the passenger side flow past 2,3,4 90 deg turns to the main bearings so they get fed better. several people much smarter than me swear by this mod.

 

[Newbomb Turk]

it is a 3/8 copper tube from the pass oiling gallery over to the drivers side oiling gallery then the passenger side front oil gallery feed down to the #1 main is blocked & the #1 main is fed from the drivers side gallery. this slow down the passenger side flow past 2,3,4 90 deg turns to the main bearings so they get fed better. several people much smarter than me swear by this mod.

Ok. They are wrong. It was done if you block off the oil at the number 1 main.

Slowing the oil down isn’t true. It just shows they don’t understand basic hydraulics.

You can do it, just don’t expect it to make the oiling system better other than the fact you aren’t pulling any oil off the number 1 main. Which only feeds one rod bearing anyway.

 

[Rapid Robert]

I googled Sanborn (a deceased guru here on FABO) & there is some heated pro & con conversations regarding this. I will dig in further & definitely give alot of thought/weight to your info. thank you. RR

 

[Newbomb Turk]

I googled Sanborn (a deceased guru here on FABO) & there is some heated pro & con conversations regarding this. I will dig in further & definitely give alot of thought/weight to your info. thank you. RR

I talked to him a couple of times before he passed. Really a nice, smart guy. I don't recall reading his stuff or talking to him where he said the crossover tube slowed the oil down. He may have, but I don't remember it.

If you are going to do the crossover to not pull oil off the number 1 main to feed the drivers side lifters I say do it. If you are doing it because its going to slow the oil down to make the corner then it doesn't help.

 

[Duane]

I talked to him a couple of times before he passed. Really a nice, smart guy. I don't recall reading his stuff or talking to him where he said the crossover tube slowed the oil down. He may have, but I don't remember it.

If you are going to do the crossover to not pull oil off the number 1 main to feed the drivers side lifters I say do it. If you are doing it because it’s going to slow the oil down to make the corner then it doesn't help.

Sanborn went further than that.He ran a separate line from the oil filter area to the front of the main oil galley feed on “X” blocks. He did indeed vouch for the many oiling problems the small block has when raced. Hydraulics does not totally apply. It is not a sealed system. There are leaks everywhere. This has been well discussed on here.

 

[Newbomb Turk]

Sanborn went further than that.He ran a separate line from the oil filter area to the front of the main oil galley feed on “X” blocks. He did indeed vouch for the many oiling problems the small block has when raced. Hydraulics does not totally apply. It is not a sealed system. There are leaks everywhere. This has been well discussed on here.

Yes it has. And the error of what the crossover does is still being spread like the clap in a high school locker room. I also didn't agree with the line up to the front unless it is the only feed. Having opposing feeds in the same gallery can stop flow at some point in the pipe.

Hydraulics always apply. Even in a constant flow system like the oiling or mechanical fuel injection. Classic hydraulics is high pressure, low pressure and return. With these systems you only have pressure and return. There is only one pressure (although the pressure varies at different points in the system) and return, and the return is where the leaks are.

You can reduce the leaks but you always have to have them. My end point is adding the crossover to slow down the oil isn't going to slow down the oil flow. Oil flow will always be the end leak. Big leak, big flow.

The crossover modification has it's place, but using it to slow oil flow isn't one of them. That's why I asked Robert why he was doing it. If it's only to slow the oil down he's wasting time and money.

 

[92b]

Having opposing feeds in the same gallery can stop flow at some point in the pipe.

What hydraulic principle is at work to cause this?

 

[Duane]

What hydraulic principle is at work to cause this?

Yes a contradiction in his reply. If it is strictly based on hydraulics and the idea is that pressure goes everywhere, then how can an equal but opposite direction, stop the flow.
It doesn’t, but it sure cuts the speed or velocity down, leaving the oil nowhere to go, but to the main bearings. I have a friend that ran a small diameter line to the back of his big block for the same reason. Big blocks
oil from the front of the galley, but same principle.

 

[Newbomb Turk]

What hydraulic principle is at work to cause this?

Think it through. If you have 80 PSI at one end of a pipe (oil gallery in this example) and lets say 70 PSI at the other end of the pipe then you can understand that somewhere in that length of pipe there will be pressure but no flow. And the point of no flow can move back and forth in the pipe as the different leaks off of the pipe come and go.

Of course, if you have full groove mains then some oil is always going out to the rods but even then the leak at the bearing will be more when the the oil holes are lined up in the crank and block.

So just sticking an extra feed line in the system isn't the answer.

Thinking about it...if I were to do something like that when I tubed the block I would close of the ends of the pipe where they meet in the middle. Then you'd be feeding 2 mains from one feed and 3 from the other.

So no contradiction at all. You can have pressure and no flow. It happens in fuel systems all the time. Well, not as much any more because fuel systems have gotten better. But I still see it every now and then.

These oiling systems are simple hydraulics. System pressures vary a bit, say from what the gauge says and what the rockers and shafts see.

When I bought my first W2 engine the oiling system (for a wet sump) was sorted out. After a year I took it down for freshening and upgrades. And everyone to a man except me wanted to change it. That required removing some plugs blocking the feed from the lifter gallery. Once those came out, I couldn't keep a rod bearing in it to save my ***. Then I hurt the crank and when I did that it got worse because no one would cross drill it. Eventually I did cross drill it myself and I put the restrictors back in where they went. I NEVER hurt another bearing, even when losing focus ad shifting at 9k rather than 8500.

Like porting heads, you have to know where the oil is going and WHY it's going there. If you don't, it's a crap shoot on bearing survival.

To sum it up, the cross over has its place but its not some secret squirrel **** voodoo magic. It's pure hydraulics. And to that end, IMO guys need to spend way more time on the pickup side of the pump and not the other stuff. The biggest restriction in the oiling system is the suction side of the pump, not on the pressure side. Get the inlet to the pump as big as you can, use a rear sump pan, full groove bearings, stop the leaks at the lifters and you can shift at 9k plus and not hurt a bearing. If you don't' do the former but add the crossover you didn't fix anything.

 

[92b]

Think it through. If you have 80 PSI at one end of a pipe (oil gallery in this example) and lets say 70 PSI at the other end of the pipe then you can understand that somewhere in that length of pipe there will be pressure but no flow. And the point of no flow can move back and forth in the pipe as the different leaks off of the pipe come and go.

The way I understand hydraulics is if you have pressure even if it is supplied to each end of the pipe as long as there is an area of lesser pressure in the system there will be flow to that area of lesser pressure.

 

[Newbomb Turk]

The way I understand hydraulics is if you have pressure even if it is supplied to each end of the pipe as long as there is an area of lesser pressure in the system there will be flow to that area of lesser pressure.

That's correct. You can have pressure and no flow, and we have remember that these engines are over pumped. Well most of them are anyway and probably should be. At low engine speeds with a big pump and not much oiling moving through the engine you can have pressure and no flow.

If you want me to tell you the crossover is some magic bullet I won't because its not.

All it will do is move oil from the passenger side to the drivers side lifter bank. 99.9% of the guys I know who have done it still feed oil up from the number 1 main. It can't slow the oil down to make the turn or any other of the garbage that's been published about it. It has never saved a single bearing because it can't.

 

[92b]

That's correct. You can have pressure and no flow, and we have remember that these engines are over pumped. Well most of them are anyway and probably should be. At low engine speeds with a big pump and not much oiling moving through the engine you can have pressure and no flow.

If you have pressure with no flow, then you have a sealed system. If you have pressure and oil moving through the system then you have flow.

If you want me to tell you the crossover is some magic bullet I won't because its not

I haven't mentioned the cross over hose.

 

[Newbomb Turk]

If you have pressure with no flow, then you have a sealed system. If you have pressure and oil moving through the system then you have flow.



I haven't mentioned the cross over hose.

I know you didn't but that's what started this thread and I don't want to lose sight of that.

I agree with your first statement except to say you can have leaks and no flow or severely restricted flow.
Everyone is so convinced that rod bearing failures happen because the oil is moving too fast down the oil gallery and that's just not true.

What kills the 3-4 and 5-6 rod bearings is the fact that we are stealing oil off the 2 and 4 mains to feed the rockers and shafts. And the issue is far worse with a roller cam because all of them have a groove around the 2 and 4 cam bearings to give them full time oiling.

That's what kills the rod bearings. That and RPM. And I suppose (as I can't prove it yet) part of that is the pump is on the bypass at some point and even though its on the bypass it can't put enough oil out to feed the rod bearings at high RPM because of all the leaks at the rockers and adjusters.

 

[92b]

Having opposing feeds in the same gallery can stop flow at some point in the pipe

I still don't understand what hydraulic principle is at work to cause this.

 

[Newbomb Turk]

I still don't understand what hydraulic principle is at work to cause this.

Then it doesn’t happen, even though it does. I don’t know how else to explain it.

The same thing happens to the fuel system except we are dealing G forces. You can have full pressure on the gauge and ZERO flow.

If the crossover was the **** everyone would do it on everything that is laid out like a Chrysler. But they don’t.

If it worked you’d see lines running everywhere. You don’t.

You can have pressure and zero flow. So running two columns of oil together from opposite direction will cause at some point full pressure and zero flow.

I’m going to have to get a small Chevy block and crank here and make a video so I’m not typing the same **** over and over.

Looking at those two systems you’ll find that one will oil to 10k on stock parts and the other won’t run reliably to 8k without a ton of work, regardless of all the bullshitters claiming they were doing it back in the day.

Then look at both of them and you’ll see why that is. How much and when the oil gets to where it needs to be is critical. Chrysler missed on both and a crossover won’t fix that, which was the point of my first post.

It doesn’t fix anything. It’s used to put oil to the drivers side lifters when the OE feed is blocked.

Why do you think a BBM will kick the 5-6 rods out? Do you think the cross over would fix that? Of course it won’t. It can’t because even if you did a crossover you aren’t fixing the issue and that’s feeding both rocker shafts off the same main bearing PLUS the oil timing to the rods is off. RPM makes it worse.

So whether or not you can grasp that you can have pressure and no flow, or whether you grasp that you can over pump the engine and band aid it, you have to address the root cause of the failures. And you can’t show me a single example of the crossover slowing oil down to make a turn.

It’s a constant flow system and once you have pressure the flow is controlled by the leaks. Again, the crossover tube does not and can not slow the oil down an IF it did how would that solve the issue of taking oil from the mains to feed the rockers?

Answer: it can’t.

 

[92b]

Then it doesn’t happen, even though it does. I don’t know how else to explain it.

What are you seeing the evidence that leads you to believe that pressure feeding from opposing ends of a gallery stops flow at some point along the gallery. Is there a hydraulic principle in a book or some where on the Google machine that that explains how this could happen? I might be persuaded if there was an explanation for the physics behind this. Maybe Pascal's law can explain it.

The same thing happens to the fuel system except we are dealing G forces. You can have full pressure on the gauge and ZERO flow.

I can see how G forces could affect flow in a fuel system during a hard launch. But I don't think we are talking about the loss of oil flow from a hard launch. So I don't see how that relates to pressure feeding from opposing ends of a gallery.

 

[Duane]

I googled Sanborn (a deceased guru here on FABO) & there is some heated pro & con conversations regarding this. I will dig in further & definitely give alot of thought/weight to your info. thank you. RR

Hey Robert. I am a firm believer that the crossover mod works to slow oil velocity, when properly done. Having said that, I have never done that method because the angles that you are asking about have to be done right or it doesn’t work. Imho it is not a diy
Job. I found the tubing of the main gallery
Easier for a diy to perform.
The crossover mod has evolved to where sisters think it is just a matter of putting in two fitting and connecting any old tube.
That is why

The way I understand hydraulics is if you have pressure even if it is supplied to each end of the pipe as long as there is an area of lesser pressure in the system there will be flow to that area of lesser pressure.

Thankyou. Although I do agree with one part of his explanation. Feeding both ends cut the flow in the galley. Which is exactly what is desired. The pressurized oil has nowhere to go but to the low pressure area at the bearings, which is exactly what we want. The problem with the stock system, is there are too many other places for the oil to go.

 

[Newbomb Turk]

What are you seeing the evidence that leads you to believe that pressure feeding from opposing ends of a gallery stops flow at some point along the gallery. Is there a hydraulic principle in a book or some where on the Google machine that that explains how this could happen? I might be persuaded if there was an explanation for the physics behind this. Maybe Pascal's law can explain it.


I can see how G forces could affect flow in a fuel system during a hard launch. But I don't think we are talking about the loss of oil flow from a hard launch. So I don't see how that relates to pressure feeding from opposing ends of a gallery.

Take two pieces of 1/2 inch pipe, drill four 1/2 holes in it and put the ends together. Then drill 4 hole in the top that don’t line up with the lower holes and stick gauges in them. Put a hose on each end with a regulator and measure the pressure at them.

What I can’t understand is why you are hung up on this.

To end this horseshit I’ll say I’m wrong. Then you explain to me how a crossover tube fixes anything.

I couldn’t care less what you think about anything except why you think a crossover works.

**** me

 

[Newbomb Turk]

Hey Robert. I am a firm believer that the crossover mod works to slow oil velocity, when properly done. Having said that, I have never done that method because the angles that you are asking about have to be done right or it doesn’t work. Imho it is not a diy
Job. I found the tubing of the main gallery
Easier for a diy to perform.
The crossover mod has evolved to where sisters think it is just a matter of putting in two fitting and connecting any old tube.
That is why

Thankyou. Although I do agree with one part of his explanation. Feeding both ends cut the flow in the galley. Which is exactly what is desired. The pressurized oil has nowhere to go but to the low pressure area at the bearings, which is exactly what we want. The problem with the stock system, is there are too many other places for the oil to go.

Straight nonsense. Oil speed has ZERO to do with bearing failures and you have zero proof it slows the oil down and even if it did it wouldn’t fix the underlying issue.

 

[Newbomb Turk]

I just went and grabbed my 1978 mopar book to read up on the crossover.

It’s total nonsense. If the pressure stays the same with the crossover then oil speed is the same and it is NOT an oil speed issue. Read through it. Everything they do is to get oil from the lifters to the mains. If you are running solid lifters, why would you want ANY oil at the drivers side oil gallery. You wouldn’t.

That whole part of the book is nonsense.

You show me from an hydraulics engineering book that you can change oil speed at the same pressure. I’d love to read it.

In the end you can’t block off oil to the drivers side bank and then put it back and tell me you fixed anything.

Edit: I forgot to mention that if you run hydraulic lifters you have to put oil back to the drivers side. There are better ways to do it than a crossover tube.

Same goes for pushrod oiling. If you are going to oil through the pushrods then you have to put oil back there. There are better ways to do that than a crossover.

The crossover is the answer to nothing.

 

[Duane]

I googled Sanborn (a deceased guru here on FABO) & there is some heated pro & con conversations regarding this. I will dig in further & definitely give alot of thought/weight to your info. thank you. RR

Hey Robert. I am a firm believer that the crossover mod works to slow oil velocity, when properly done. Having said that, I have never done that method because the angles that you are asking about have to be done right or it doesn’t work. Imho it is not a diy
Job. I found the tubing of the main gallery
Easier for a diy to perform.
The crossover mod has evolved to where sisters think it is just a matter of putting in two fitting and connecting any old tube.
That is why

Thankyou. Although I do agree with one part of his explanation. Feeding both ends cut the flow in the galley. Which is exactly what is desired. The pressurized oil has nowhere to go but to the low pressure area at the bearings, which is exactly what we want. The problem with the stock system, is there are too many other places for the oil to go.

Sorry I forgot to finish a previous post to Rapid Robert. At the end I was starting to say that the crossover tube requires the angles of the drilled passages to be very specific for it to work. I never performed this because imho it is not diy friendly.
The crossover mod had been misunderstood to the point that it is just a matter of hooking up any old tube and connect it to the other galley. Not so. The angles of the fitting are very important. It should also be mentioned that the originator of the crossover tube is none other than famed Bob Mullen a Chrysler engineer and Bob Glidden. AFAIK this mod was developed for the Mullen designed W2 pro stock motor that Glidden drove. The other thing if my memory serves is that the tube is only one part of the mod.
The number one main is reverse fed from the drivers side galley. This reduced velocity
In the passenger side galley because you don’t have all the oil at number one main
Trying to feed 8 lifter bores on the drivers side. I always viewed tubing the block as easier for the diy person to perform.

 

[Duane]

I just went and grabbed my 1978 mopar book to read up on the crossover.

It’s total nonsense. If the pressure stays the same with the crossover then oil speed is the same and it is NOT an oil speed issue. Read through it. Everything they do is to get oil from the lifters to the mains. If you are running solid lifters, why would you want ANY oil at the drivers side oil gallery. You wouldn’t.

That whole part of the book is nonsense.

You show me from an hydraulics engineering book that you can change oil speed at the same pressure. I’d love to read it.

In the end you can’t block off oil to the drivers side bank and then put it back and tell me you fixed anything.

Edit: I forgot to mention that if you run hydraulic lifters you have to put oil back to the drivers side. There are better ways to do it than a crossover tube.

Same goes for pushrod oiling. If you are going to oil through the pushrods then you have to put oil back there. There are better ways to do that than a crossover.

The crossover is the answer to nothing.

Drivers side or passenger side.