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help have been looking for normal oil pressure for 1989 ford 302 eng i now have 60psi on stock eng was thinking it should be around 30 psi what is the right oil pressure thanks
 

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Oil pressure varies alot due to temp and rpms as well as the weight of the oil you are running..It would be helpful if you listed your pressures at cold and hot temps and also at what rpms?..Of course if the engine has been rebuilt and is running an aftermarket oil pump that can change pressures as well...If your running 60 psi with a cold engine I would say that is pretty normal..
 

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help have been looking for normal oil pressure for 1989 ford 302 eng i now have 60psi on stock eng was thinking it should be around 30 psi what is the right oil pressure thanks
hot or cold . at idle or 10Krpm ?
 

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The Right oil pressure is anything that keeps your engine lubricated safely at any rpm.

Nominally 10 psi per 1000 rpms. That's about as undiluted an answer as can be given...
 

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And since oil pressure is just an indirect measurement of how much oil leaks past your bearings, bearing clearances have a huge impact. My own 1989 302 with 10W-30 oil is 55 psi cold, 35-40 psi hot, at 2000 rpm where the Ford service manuals used to tell you to check at.
 

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Discussion Starter · #8 ·
thanks i had just got it runing it had ben setting for a long time it was cold eng ran it for 5 min and was at 60psi 10w 40 oil have not turned wrenches for a long time and its good to be back to turning them agin just forgot some of the things its ben some thing like 20 years or so and i have ADHD and copd now and old age too its comeing back a little at a time i will make it thanks for all the help #1spudman :tup:
 

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Now that is definetely NOT normal.
All depends on the type of oil pump (HI-PRESS/HI-VOL/Both) and how tight the engine was assembled. Remember, JCs' is a Police Engine also while 90 cold is a bit much but the engine does a have pressure relief valve (HP).

You need to plot a graph (cold and hot) of pressures at different RPM'S.

30 @ idle and 60 under load is a damn healthy engine (IMO).
 

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All depends on the type of oil pump (HI-PRESS/HI-VOL/Both) and how tight the engine was assembled. Remember, JCs' is a Police Engine also while 90 cold is a bit much but the engine does a have pressure relief valve (HP).

You need to plot a graph (cold and hot) of pressures at different RPM'S.

30 @ idle and 60 under load is a damn healthy engine (IMO).
I agree!
 

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I'd say the only real qualifier of "too much" is:

A) if you snap your pump shaft
B) If you pop your galley plugs out
C) If you pump your pan dry
 

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I'd say the only real qualifier of "too much" is:

A) if you snap your pump shaft
B) If you pop your galley plugs out
C) If you pump your pan dry
I would add:

D) If your distributor gear or cam gear show excessive wear
E) If you mind wasting fuel making horsepower to pump more oil than it needs
F) If you don't want to add any more excess heat to your oil
G) If you don't want to add additional oil drag to your windage at high rpm
H) If you don't want to add additional load or drag to your piston oil rings
I) If it ever exceeds the working pressure of your oil filter or gasket

David
 

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Also, high pressure/flow for whatever reason when cold will open the filter bypass if pressure differential exceeded. This may not be considered desirable. Another thing, in colder climates where oil thickening is common, even with the bypass open, the differential may exceed the structural capability of the element causing it to distort or crush. This usually goes undetected since few people cut open their filters to inspect. Synthetic oils can reduce this.
 

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And this is why engine lubrication design is different between passenger car and HP/Police engines. One must understand the ramifications of modifying.
 

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And this is why engine lubrication design is different between passenger car and HP/Police engines. One must understand the ramifications of modifying.
what is the difference klutz in the oiling systems ?
 

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And since oil pressure is just an indirect measurement of how much oil leaks past your bearings, bearing clearances have a huge impact. My own 1989 302 with 10W-30 oil is 55 psi cold, 35-40 psi hot, at 2000 rpm where the Ford service manuals used to tell you to check at.

exactly. Pressure (no matter what kind of pressure we're talking about) is a product of leakage. A worn out engine will always have larger clearances and a higher leak rate, therefore lower oil pressure. Take a garden hose and put a gauge between the hose and the spigot on the house. Turn the hose on, wide open at the end. Zero pressure. Now put your finger over it and watch pressure climb.

It helps, when building this stuff (or repairing it) to know a little about simple physics :)
 

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I wouldn't say pressure is always a product of leakage, but rather the converse, in that it is pressure that creates flow.
 

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I wouldn't say pressure is always a product of leakage, but rather the converse, in that it is pressure that creates flow.
right , no pressure unless there is a restriction . pumps don't make pressure , restriction does
can have flow with no pressuse though

example of hose and spigot , gage at spigot and very long run of open hose and high water flow , gage can read a psi .
 

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right , no pressure unless there is a restriction . pumps don't make pressure , restriction does
can have flow with no pressuse though

example of hose and spigot , gage at spigot and very long run of open hose and high water flow , gage can read a psi .

I'm not sure if you're agreeing with me or not. I guess you're putting the gauge on the hose side of the spigot. But yeah, if you're talking pressure losses, the pressure is maximum at the spigot and minimum at the open end.

It's the same thing out here in the oilfield. Pumping pressure may be 2500psi on surface, but maybe 200 psi at the bit - a lot of people confuse pump pressure with output pressure in a long fluid run.

But yes, pumps don't make pressure unless they have something to pump against. The pressure capability of an impeller pump depends on the flow rate. Not necessarily true with a positive displacement pump. Fluid PD pumps are capable of breaking themselves if they don't rupture pipe first.
 
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