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fresh 440 build has 90 lbs of oil pressure at idle

I use 30 or 10w 30 (we will probably never see the "w" active in FL) in everything unless it's wore out.

I did use 40 or 20/50 in my 100K plus old HiPo cars.

Agree about hi vol/ hi press pump- not really necessary.

I sure hope you get this sorted out.
 
Oil pressure = oil flow. High oil pressure = high (or faster) oil flow. Means flow is too fast, to pull heat from the parts, it lubes, and cools a little.

440. 55 lbs oil pressure, at highway speeds, pretty normal.

That's the way I see it...
 
high pressure is resistance to flow. it doesn't mean there's more flow/volume; just resistance to more flow/volume.
 
That depends on clearances, and if the sending unit is reading correctly. Sending unit sensor only reads, what it gets.
 
miller said:
Oil pressure = oil flow. High oil pressure = high (or faster) oil flow. Means flow is too fast, to pull heat from the parts, it lubes, and cools a little.

440. 55 lbs oil pressure, at highway speeds, pretty normal.

That's the way I see it...
Click to expand...


I usually avoid commenting on these types of statements as it usually turns into a circular discussion on the opinions of what folks think.

Although there are a host of exceptions, generally fluid flow and heat transfer follow these rules:

1) Fluid flow will be proportional to the square of pressure in turbulent conditions. So a going from 60 psi to 90 psi will result in a 22% increase in flow to the bearings (total flow from the pump is even more due to the relief valve opening more as pressure goes up)

2) Heat transfer will generally increase proportionally (or potentially more) with increase flow (i.e. increase cooling)

3) Because of gerotor pumps are positive displacement pumps, volume continues to go up more than what's pumped to the engine through the relief valve (otherwise pressure would go up even more) requiring a lot of work by the pump. Most of this pump work is transferred to the oil in the form of heat.

At the end of the day, no one is going to damage an engine due to oil temperature from increasing pump pressure and volume in the context of this discussion. But it is of no benefit at all to use more pressure and and even worse, pressure & volume, than needed and is harder on parts.
 
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BSB67 said:
I usually avoid commenting on these types of statements as it usually turns into a circular discussion on the opinions of what folks think.
Click to expand...
Agree. Also with most of your other statements.

BSB67 said:
3) Because of gerotor pumps are positive displacement pumps, volume continues to go up more than what's pumped to the engine through the relief valve (otherwise pressure would go up even more) requiring a lot of work by the pump.
Click to expand...
I don't fully agree with all of this one.
Yes, volume can easily be increased. Again, it depends on the engine's clearances. That creates pressure, along with the pressure relief valve. Adjusted as needed.

Nope...not trying to make any claims, going by past experiences...on radial engines!
Why?? Same principals, basicly, same parts and pieces, all needing oil pressure, and volume.
Auto engine's crank journals, vs bearing clearances, usually fairly close. Radials are completely different, but still need the oil, both ways.
R-1820 radial...crank has ONE rod journal, to service nine cylinders. The one rod bearing (one piece), about 4" wide, about 4" diameter, the measured 'clearance' from bearing to journal, is only 1/2" wide, in the center of the bearing. Tapered wider at both ends. So what?
Takes oil pressure, to keep that small area separated, along with the volume. Point is, pretty much nowhere in those engines, including that bearing, that creates pressure. All free flow.
Only the pressure relief valve creates pressure, the restriction it creates.

But, the thinking is there. Done.
 
miller said:
Agree. Also with most of your other statements.


I don't fully agree with all of this one.
Yes, volume can easily be increased. Again, it depends on the engine's clearances. That creates pressure, along with the pressure relief valve. Adjusted as needed.

Nope...not trying to make any claims, going by past experiences...on radial engines!
Why?? Same principals, basicly, same parts and pieces, all needing oil pressure, and volume.
Auto engine's crank journals, vs bearing clearances, usually fairly close. Radials are completely different, but still need the oil, both ways.
R-1820 radial...crank has ONE rod journal, to service nine cylinders. The one rod bearing (one piece), about 4" wide, about 4" diameter, the measured 'clearance' from bearing to journal, is only 1/2" wide, in the center of the bearing. Tapered wider at both ends. So what?
Takes oil pressure, to keep that small area separated, along with the volume. Point is, pretty much nowhere in those engines, including that bearing, that creates pressure. All free flow.
Only the pressure relief valve creates pressure, the restriction it creates.

But, the thinking is there. Done.
Click to expand...

What I've stated is not an opinion.
 
BSB67 said:
I usually avoid commenting on these types of statements as it usually turns into a circular discussion on the opinions of what folks think.

Although there are a host of exceptions, generally fluid flow and heat transfer follow these rules:

1) Fluid flow will be proportional to the square of pressure in turbulent conditions. So a going from 60 psi to 90 psi will result in a 22% increase in flow to the bearings (total flow from the pump is even more due to the relief valve opening more as pressure goes up)

2) Heat transfer will generally increase proportionally (or potentially more) with increase flow (i.e. increase cooling)

3) Because of gerotor pumps are positive displacement pumps, volume continues to go up more than what's pumped to the engine through the relief valve (otherwise pressure would go up even more) requiring a lot of work by the pump. Most of this pump work is transferred to the oil in the form of heat.

At the end of the day, no one is going to damage an engine due to oil temperature from increasing pump pressure and volume in the context of this discussion. But it is of no benefit at all to use more pressure and and even worse, pressure & volume, than needed and is harder on parts.
Click to expand...
discussion goes around in circles; yep! change opinions; nope. i'm moving on. have a nice sunday friend!
 
Chief complaint is a new Engine with 90 psi Oil Pressure/to the point of damaging Oil Filters, with some dissatisfaction of builder continuity as reason for seeking advice here.
Just put a std volume Oil Pump on it, then use lighter Oil.... and keep going to lighter and lighter Oil as req'd until you get somewhat "normal" Oil Pressures.

What I still don't understand though, is how in the heck you get a supposedly Performance Engine built ? and nobody seems to know diddly about it ?
Like WTF the internal Engine Bearing Clearances are ?

Your Spec Sheet is a bunch of "jibberish" as far as I'm concerned.... tells you nothing beyond it's got a 284/296 Cam, Torker Intake ? Moly Rings ? WTF is that ?
Do you even know what Pistons are in the Engine ? Seeing as ALL rebuilder cast stock Pistons are lucky if you get 8:1 Compression ?

Oh I get it.... Bearing Clrcs were "within specs" right ?

Negative Nancy out,
IMO, you GOT exactly what you PAID for ?
That being an extremely bargain basement rebuilder style 8:1 440 Engine. albeit, with a HUGE Cam and Intake.



 
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OPs problem is 90psi at idle?...why so much. Changing relief spring is a band-aid in this particular situation, is that a safe assumption? (Please correct me if I'm way off here, guys that know this stuff way more than I do! Here to learn...) If the pump was worn/failing, wouldn't that cause lower, not higher, pressures? Especially at idle speed?That leaves the engine side of things. Restrictions somewhere. As stated earlier pressure is a function of the restrictions of the flow path, so that would have me leaning toward --real tight clearances needing a much thinner oil, or something's got a blockage somewhere? If messing with the pump seems to fix it, okeedokee then, but it just seems to me there's an underlying cause that likely has nothing to do with the pump.
 
How about this for a possibility....rocker shafts installed the wrong way, blocking off the oiling pedestals and dead-heading the system? I could be in left field on that one, but it's an easy check..
 
if i were u,,i would install the Milodon Externally Adjustable Oil Pressure Regulators 21550
,,dial in the pressure u want,,i have been using these for 10 years now and they go in every motor i have,,i just set oil pressure on the engine stand at 60 lbs before recently installing it,,ready to go,,

https://www.summitracing.com/parts/mil-21550
 
lewtot184 said:
discussion goes around in circles; yep! change opinions; nope. i'm moving on. have a nice sunday friend!
Click to expand...
Miller,
I agree wholeheartedly with your premises. Obviously, many of the contributors have not heard of or believe in the hydrodynamic principle of Boyle's Law: Pressure varies DIRECTLY with Temperature and Inversely to Volume. This relates to bearing clearances (tighter the clearance [smaller the number] the lower the volume but higher pressures) the pump (with a given displacement) will produce. Because the pump (geroroter) is a positive displacement pump, it will try to supply the volume the system requires. Perhaps the person that noted that his oil filter gasket failed, he should consider a different brand (Wix or ???).
The rotating member actually floats on a HYDRODYNAMIC WEDGE of oil when operating......the crankshaft actually is suspended on wedge of oil between it and the bearing surface. Google hydrodynamic principles relating to crankshaft oiling for a good understanding. Perhaps, some of the contributors should research the subject so they can speak from a knowledgeable stand point rather than speculating or their own opinions.
BTW....I use a high VOLUME pump with 10W-30 Mobil One with 0.002" - 0.0025" (full gtoove main bearings) and rod bearings clearances. Pressure at cold start is 75-80 psi @ 2000RPM; Pressure at hot running is 70 - 75 psi @ 3000RPM; Pressure at hot idle is 50 -55 psi @ ~ 1200RPM. I use a Fram HP-1 filter with out problems. According to some, this is OK, others may disagree. Again, the above is my opinion.
Bob Renton
 
Jesus Chrysler. As long as the factory gauge even stirs, I’ll drive it. Pegged at start up for years with no ill effects.
 
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Funny. Boyles law is exclusively an ideal gas law, which has no relevance what so ever to this.
 
The OP's problem was solved in post #4. The rebuild obviously has tight clearances and extremely doubtful that full grooved main bearings were used. The HV pump along with the black pressure relief spring and conventional oil all contribute to the high cold start oil pressure. The HV pump is moving more oil volume than the standard pump through tight bearing clearances, thus the higher pressure.

Install the red spring, and if the oil psi is now too low, install the Milodon adjustable tension kit, which by the way, is designed to increase the pressure with a light spring....it won't help this situation with he black spring, it already has too much tension. Back in the day we used to shim the red spring to tweak the oil psi up. 6,000 rpm requires 60 psi minimum.
 
I stand corrected...Boyle's Law deals with gases. Crane's Flow of Fluids and Goulds Pump Manual deals with pumped liquids, Although Flow of Fluids desls with liquids, air is also considered a fluid, subject to similar to constraints. I would suggest reading at the Goulds Pump Manual to see the volume pressure relationship....specifically the pump's operating curve. It also uses temperature, viscosity and pump efficiency to make a determination.
BSB67 said:
Funny. Boyles law is exclusively an ideal gas law, which has no relevance what so ever to this.
Click to expand...
Bob Renton
 
RJRENTON said:
I stand corrected...Boyle's Law deals with gases. Crane's Flow of Fluids and Goulds Pump Manual deals with pumped liquids, Although Flow of Fluids desls with liquids, air is also considered a fluid, subject to similar to constraints. I would suggest reading at the Goulds Pump Manual to see the volume pressure relationship....specifically the pump's operating curve. It also uses temperature, viscosity and pump efficiency to make a determination.

Bob Renton
Click to expand...
Been designing fluid transfer and hydraulic systems for 35 years. I may, or may not specify a Gould pump when I'm interested in using a centrifugal pump. Of course, that's not applicable to what we're discussing here either.
 
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