options for oil pressure/flow balance lines

pila78

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Nice looking plumbing Dave ! :D I like those long radius elbows....
I decided not to fool with mine. Would like to find another engine first....








Bill
 

dave brode

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pila78 said:
Nice looking plumbing Dave ! :D I like those long radius elbows....
I decided not to fool with mine. Would like to find another engine first....

Bill

Thanks, Bill.

Imo, rather than the complication of the tee and going behind the flywheel, running a simple single line to the gauge port behind the intake would help on any engine. Doing so should greatly reduce the oil going from the pass side header through the cross-over, therefore keeping more oil in the problem pass side. One could run it up and back along the valve cover in hard line. Not as good, but still good.

Dave
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The Mad Cadder

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dave brode said:
pila78 said:
Nice looking plumbing Dave ! :D I like those long radius elbows....
I decided not to fool with mine. Would like to find another engine first....

Bill

Thanks, Bill.

Imo, rather than the complication of the tee and going behind the flywheel, running a simple single line to the gauge port behind the intake would help on any engine. Doing so should greatly reduce the oil going from the pass side header through the cross-over, therefore keeping more oil in the problem pass side. One could run it up and back along the valve cover in hard line. Not as good, but still good.

Dave
ް

Very much agreed! And was my original plan until member 3508 directed me
to the Balance Line Thread...

Dave ,

your right the Braided Stainless Lines are a GIANT PAIN IN THE %$#
 

Darius

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Gentlemen,

One question that comes to mind is: What are we trying to accomplish with the various schemes to take oil to the rear of the engine? I know that the passenger's side toward the engine's rear has in some cases suffered from a lack of oil due to "leaks" that occur prior to the oil arriving at that point. Therefore the bypasses.

But is that simply a problem of location (farthest away) or of inadequate volume to overcome the prior leaks?

As my current engine build was being put together choices were made about rod, side and main bearing clearances all in an effort to lessen those leaks - but with the possibility of not providing sufficient oil when under heavy engine strain. Like many things that decision involved tradeoffs.

My project is further complicated in that the two rear mounted turbochargers need to be oiled - not only to lubricate their bearings but also for the motive power of the pressurized oil which operates the variable vanes on each unit. That is one reason my engines clearances were kept tight as I knew that oil would be needed for the turbos thereby putting an even greater strain on the oil available.

Now to a question, or possible solution.

In the past I was part of the Chevy Corvair community. In that community high output conversions for the Corvair stock oil pump have long existed. The picture here shows the type of approach used. An simple spacer is sandwiched between the engine and pump body. The extra space allows for two taller gears to be used. A longer drive shaft is provided with the kits and all together an additional 30% - or more - in volume is gained. Why hasn't something along those lines been proposed/developed for the Cadillac engines? What are the design limitations?

My logic says that rather than buying expensive aftermarket oil pumps a straightforward increase in pump output would provide whatever volume was deemed beneficial to run wider clearances without shorting distant bearings. That higher volume would also have the effect of increasing pressure as a function of resistance to the greater flow.

Your thoughts.

Best,

d
 

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The Mad Cadder

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D,

I believe the Cadillac pump already has the longest gears avalible without making
custom length replacements...

You very well might be on to something with reduced
clearence...mine old motors all had less then what is the current take on that...
And I had not seen the starvation

.0015 to .002 rods . .around .0025 mains and rod side within factory spec
 

pila78

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I remember some folks using BBC pumps on SBC engines, but then someone mentioned that the bigger pump created rotational pulses or chatter, causing spark scatter from the distributor. Don't understand why, since the BB used the pump OK (????) on the same distributor...
 

The Mad Cadder

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pila78 said:
someone mentioned that the bigger pump created rotational pulses

Funny you brought that up because.. I see pulsation in the oil pressure gauge and have never saw this before, but Ive also never ran a -4 line to the gauge...

Also wondering if you see say 20 psi at the rear port how much do you think is left down at the rods ??
 

dave brode

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The Mad Cadder said:
[

Also wondering if you see say 20 psi at the rear port how much do you think is left down at the rods ??

The pressure port is on the rear of the dr side header. That's what the rearmost main and rod are seeing. I'd be more curious as to what the rear of the pass side header is seeing.

Dave
 

The Mad Cadder

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dave brode said:
The Mad Cadder said:
[

Also wondering if you see say 20 psi at the rear port how much do you think is left down at the rods ??

The pressure port is on the rear of the dr side header. That's what the rearmost main and rod are seeing. I'd be more curious as to what the rear of the pass side header is seeing.

Dave

Since mine are both plummed into from the remote filter mount , with individual -6 lines for both. Fed from the 2 extra ports in the mount , atleast on my setup it should be the same on all 3 feeds , including the -12 into the oil pump adapter :screwy:
 

Member 3508

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Over on V8Buick, the owner did a dyno test on a 580hp engine for the balance line. He removed the balance line and plugged in two pressure sensors (one at front, one at rear) and ran a pull.

Then reattached the balance line and plugged in a sender to the line.Interesting Results. The Buick has a similar architecture for oiling as the caddy. Long pickup tube. Front mounted oil pump. Similar splits in the lifter galley. Similar plugs front and back of the lifter galley.

All units are PSI for pressure.

WITHOUT LINE;
@3700 RPM----->64.5_Front--------->61.8_Rear
@4300 RPM----->68.1_Front--------->62.9_Rear
@5200 RPM----->75.2_Front--------->67.2_Rear
@5800 RPM----->79.8_Front--------->71.5_Rear


WITH BALANCE LINE;
@3700 RPM----->62.2
@4300 RPM----->63.5
@5200 RPM----->67.9
@5800 RPM----->72.5
 

8ad-f85

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The BBC pumps reduce the pulsing because the gears have more teeth.
The trend has been to get away from higher volume and work on the flow down the galleys, along with balance.
This is with nearly all v8's.

I think the universal problem with these is when opening up clearances to accommodate crank flex from higher power levels, the narrow bearings shed enough oil to lose load carrying capacity.
Like mentioned, I wonder what the pressure really is at the rod journal.
You can see why things were tried in the past.
AMC, Chrysler and Olds has gone through much more development since the advent of the better heads and power levels with it.
 

Roy Heisenberg

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So, with a stronger crank, and less crank flex, the oil problems go away?
 

Red98422

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So, with a stronger crank, and less crank flex, the oil problems go away?

Not necessarily, it’s the tendency of the larger clearances (which has been proven as not needed on most builds) and lack of adequate oil pump/appropriate modifications (balance lines) that lead to the issues that plague these blocks. There are also the issues of cap walk that will effect this, but that can be found in a separate thread
 

53 Studillac

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Much has been said about the Cadillac oiling system over the years and I've had as many issues as anyone as I tried to push the envelope. Others have pushed farther with more success and deserve a lot of credit. I grew up building engines with my dad but never at a blueprint level so I trusted the Cadillac guru's with my engine and money only to be disappointed. I may have said this on other post but I talked to someone at Cadco that enlightened me and I think made me realize the fundamental problem. Most of us hot rodders use a rear sump pan that required a long pick-up tube. The Eldorados that donate most of the pans do not see high RPM blast. Factory valve springs made sure of that. My opinion is the oil pump is probably large enough but the long small OD pick-up tube is just too small and causes pump cavitation at elevated engine RPMs. I like the idea of the balance tubing to the rear of the block and I plan on installing them on my next engine. But they will not eliminate the oil pump cavitation problem. Cadco explained the need for more oil volume to keep up with the larger clearances that seem to be required for big horsepower builds. If I build another engine I will go with smaller clearances and I now think they are not necessarily needed as mentioned by Red98422 above. Cadco went on to tell me they drill the passage in the block from the oil pump to the pick-up tube and fabricate a 1" pick-up tube. If I had only known before my current engine was assembled I would have done this and felt good about the stock pump being adequate. Every time I see a Chevy LS engine with the pan off I now notice the large suction line used for the rear sump pans that make the Cadillac tube look tiny. And our engine is so long it just makes it worse. Now don't get me wrong, I do not think most need to even bother. My problems have all showed up at 6500 rpm on a dyno making 700 hp. If I can get it figured out I am going to try a belt drive oil pump with an external suction line. Cadco has a lot of tricks that we could benefit from but their business model is to not share their experience. The problem with that thinking is that unnecessary lessons learned will drive people away from the big Caddy instead of driving them to their shop for business, but that is another topic.

Dwayne
 

Cadillac Kid 1

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Seemingly most of the failures have been to the rods on the last throw. With the stock oiling system that's really the end of the line on the oiling system.
Another issue is the front sump pan which is quick to send oil to the back under hard acceleration.
I thank Dave for his guidance and I have added an external line to the rear as per the pictures, and modified the oil pan to increase the capacity by about 2 quarts. That and a baffle in the pan and I should be good to go. Just putting the motor back in so we will see. Going to keep the revs under 6K which will still keep me way up into the power "band".
Thanks again Dave.
Greg Surfas
Greg Surfas oil system 39.jpg oil system 39.jpg IMG_1246.jpg IMG_1230 - Copy.jpg IMG_1230 - Copy.jpg IMG_1215 - Copy.jpg
 

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Darius

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Dwayne and Cadillac Kid,

Thank you both for the needed posts and pictures.

Dwayne, I especially agree that ultimately a philosophy of not sharing knowledge benefit no one.

I wish my opinion of Cadco has been different but it was negative due to that flawed cast oil pan of theirs.
That said, had I been more observant I too would have drilled out that oil feed passage in the block and opted for their large pickup tube. Luckily, my clearances were kept on the tight side.

Best,
bro. d
 

48Austin

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Dwayne and Cadillac Kid,

Thank you both for the needed posts and pictures.

Dwayne, I especially agree that ultimately a philosophy of not sharing knowledge benefit no one.

I wish my opinion of Cadco has been different but it was negative due to that flawed cast oil pan of theirs.
That said, had I been more observant I too would have drilled out that oil feed passage in the block and opted for their large pickup tube. Luckily, my clearances were kept on the tight side.

Best,
bro. d
What is the flaw? Not being sarcastic. Was thinking of getting one. For my gasser.
 

Darius

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Assuming that your are asking about the flaw in the Cadco cast oil pan: at least in the past they simply didn't fit properly. Guys had to do a lot of modifications before they would fit/seal. They may - or may not - be better now. I cannot say as I have never encountered one of their cast pans.

I'm saying to a fellow forum member that it might serve you well to check whether prior problems have been corrected. Below are several links along with some posts - if you do a search for, "Cadco Cast Oil Pan".

bro. d

https://cadillacmagazine.com/forums/threads/cadco-aluminum-oil-pans.10264/page-4#post-125740

https://cadillacmagazine.com/forums/threads/cadco-aluminum-oil-pans.10264/page-3#post-125345

"In all possible fairness, :scratchchin: there seems to be a question on if the CadCo ad/catalog mentions need for possible pan alterations/fitting, I didn't see any mention of this need on the site or in the catalog, but in the directions included with the pan(after sale) :irked: they do say in some applications you may have to clearence the pan, another but,to me this means only in special applications, ie girdle, studs, not a straight stock set up. Also mentions "due to casting variations, you may need to clearence the pan slightly, as well" but again doesn't say if it's the pans casting variations or Cadillac's! :yikes: "

Bruce,



" Sounds like a quality control issue to me. Pure and simple.
The part either fits or it doesn't. If they know it's not going
to fit without "modifications" they should say so and drop the
price."

"If I paid $500 for a part and it didn't fit........it would go back
immediatly where it came from. $20 Chinese parts are a different
story. You buy junk you expect to have to "massage" it to get it
to fit."


"EZ" :twocents:
 

53 Studillac

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Cadillac Kid,

Yes, same with my engines. The last pair of rods have always been the worse. And I agree the balance lines should help. But at elevated RPM I believe the suction line is the ultimate downfall. I may be wrong but no amount of re-directing flow by running lines can make the pump output more than it can draw from the pan. I'm sure the balance lines will move the rpm limit up a little more than without. No one wants to pay to figure it out! For sure the oil pressure gauge will look better because it is not reading at the end of the line any longer with the balance lines installed. 6000 rpm and 600 hp probably not an issue.

Dwayne
 
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