Hi volume oil pump vs standard volume pump

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Yes, the installed pump is/was new.
The oilpressure when cold starts out nicely at some 55-60 psi in neutral and 30+ in Drive.
But drops worryingly low when the oil starts to warm up to sub 20 and 15psi when 'warmed up'. But the engine temp never exceeds 160°F.
 
That drop from 55-60 to 30+ psi going from neutral to drive seems excessive. When you pull the present pump, I'd check all the internal clearances.

BTW, oil temps can be a good bit different from the coolant. Is petroleum oil being used? A full synthetic will typically be more stable over temps so that might help; a heavier synthetic at both weight numbers will stay thinner down at cold start temps than a petroleum oil, so that is another option for you.
 
Marcohotrod said:
in a 1/4 mile a H.V. pump will not suck a 5 quart pan dry . but in a mile I have been there, zero pressure on the gauge-my friends 327 with 4.88 gears on a street blast. Smokey tested pickups-the screen type is much better-90% open, 10% metal. the bunch of drilled round holes is 50% open
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you are saying that all 5 qts of oil are on top of the heads?......nothing is draining back....BS.....327 chevy..>>LOL....does not have the open camshaft valley like a small block dodge...probably the pickup fell out of the oil pump like most 327 do...
 
BigBlockMopar said:
Yes, the installed pump is/was new.
The oilpressure when cold starts out nicely at some 55-60 psi in neutral and 30+ in Drive.
But drops worryingly low when the oil starts to warm up to sub 20 and 15psi when 'warmed up'. But the engine temp never exceeds 160°F.
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It's not the pump, you have clearance issues.
 
nm9stheham said:
That drop from 55-60 to 30+ psi going from neutral to drive seems excessive. When you pull the present pump, I'd check all the internal clearances.

BTW, oil temps can be a good bit different from the coolant. Is petroleum oil being used? A full synthetic will typically be more stable over temps so that might help; a heavier synthetic at both weight numbers will stay thinner down at cold start temps than a petroleum oil, so that is another option for you.
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Should not see excessive pressure fluctuation with different weight oils.
 
I can relate to clearance issues, but I put the engine together myself and checked all the bearing clearances. They were all within factory spec.
I'd more inclined to point at the lifters as the problem area at the moment.

During prelubing with the intake off, I noticed some tiny bubbles forming at a few lifters.
This could be from the fact that either the lifters' oilbands are located fairly high, and/or the LA360's lifter bores have a deep camfer at the top.
I can see this bleeding off quite some pressure when the oil gets warm and thinner.

I hope to solve this by installing a HV pump and hopefully be able to go down in oil weight again a step.
 
What is your reasoning to drive around with a "cold" engine?
I assume engine temps meant water temperature, and 71°C is cold in my book.
 
70aarcuda said:
you are saying that all 5 qts of oil are on top of the heads?......nothing is draining back....BS.....327 chevy..>>LOL....does not have the open camshaft valley like a small block dodge...probably the pickup fell out of the oil pump like most 327 do...
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Yes, apples and oranges... GM designs from that era did not have the level of flow restrictions to the heads that the SBM does. The 4 bangers were really prone to over-pumping the oil into the heads with excess pressure... ask me how I know!
 
BigBlockMopar said:
I'd more inclined to point at the lifters as the problem area at the moment.
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You might want to set up a small bore gauge and check all the lifter holes while in the engine next time. There IS a spec limit on the diameter; I suspect very few folks check this.
 
70aarcuda said:
you are saying that all 5 qts of oil are on top of the heads?......nothing is draining back....BS.....327 chevy..>>LOL....does not have the open camshaft valley like a small block dodge...probably the pickup fell out of the oil pump like most 327 do...
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that`s weired, my 350/383 and 406 sbc `s did !! Unless my memory fails me, wait, I do remember drilling holes in the pockets ! LOL
 
stixx said:
What is your reasoning to drive around with a "cold" engine?
I assume engine temps meant water temperature, and 71°C is cold in my book.
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The engine runs on LPG and has a 11.3:1cr. High engine temps achieve no benefit here and only cost power due to less (hotter) mixture entering the engine. I agree the engine could be a bit warmer but don't like the engine getting too hot, get lazy and even start pinging.
I also always try to keep the intake manifold as cold as possible, but with the smallblock design with coolant running right through the intake, that's not always possible.
I'm running with a 160F thermostat, but the engine hardly gets to that temp, only occassionaly during heavy traffic where slow driving.
 
nm9stheham said:
You might want to set up a small bore gauge and check all the lifter holes while in the engine next time. There IS a spec limit on the diameter; I suspect very few folks check this.
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I did some basic checking during assembly and pre-lubing, but, lacking a proper bore-gauge at the time AND having no means of correcting any issues here, I didn't spent too much time on it.
I can probably loan the bore-gauge for the next time the engine will be opened up, which will be when the aluminium heads will be installed.
 
moparmat2000 said:
On a rebuilt engine with a mild hop up with stock bearing clearances and maybe a 5,500 rpm rev limit is a high volume pump necessary?

Does a high volume pump and higher pressure it produces actually hurt horsepower with its associated drag on an engine like this?
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No, it's not.
Yes, it does.
 
Just out curiosity, and since I am going to use the oil cooler from one, did the E58 police motor run a HV pump?
 
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My pops had a numbers matching 79 lil red express we restored years ago. Truck had 100k on it, and had never been apart until we restored it. Std engine was an E58 360. The truck had a standard volume pump in it.
 
moparmat2000 said:
My pops had a numbers matching 79 lil red express we restored years ago. Truck had 100k on it, and had never been apart until we restored it. Std engine was an E58 360. The truck had a standard volume pump in it.
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Correction on the E58 being the standard engine.
The Little red express engine was a Factory modified version of the e58.
 
What i mean about standard engine, was it was the numbers matching one installed at the factory. I believe Tom Hoover breathed a bit more life into it before it went into production over a regular E58. However the standard production engine listed for a 78 and 79 lil red express is listed as an E58 360.
 
70aarcuda said:
I use hv oil pumps on the bracket cars and my street driven duster with a stock oil pan....and it has seen a few trips down the track....and it does not pump the pan dry..LOL....old wives tales never stop....

so use what you want and makes you sleep at night....
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I would like to hear more about your street Duster, and what it ran :)
 
moparmat2000 said:
What i mean about standard engine, was it was the numbers matching one installed at the factory. I believe Tom Hoover breathed a bit more life into it before it went into production over a regular E58. However the standard production engine listed for a 78 and 79 lil red express is listed as an E58 360.
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. The Red Express engine code was EH1.

Because of a loophole in the emissions regulations the 1978 Dodge Lil' Red Express Truck's did not have catalytic converters, what the Lil' Red Express did have was a special High Performance 360 C.I. 4-barrel small block engine code (EH1) which was a modified version of the 360 police engine (E58) producing 225 net horsepower @ 3800 RPM. The package also included Hemi style mufflers with a crossover pipe breathing through 2 chrome stacks located behind the cab, a special 727 transmission and 3.55:1 rear gearing.
 
moparmat2000 said:
And so it was. I stand corrected. Always thought it was E58
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I did too but I was corrected by a fellow FABO member. We have a 78 LRE. I gave it to my wife for our 3rd anniversary about 27 years ago. It's stashed in the barn for the winter.

I put a new oil pump in it and when it warms up the pressure drops from 50 psi to around 10 psi.
 
Ok, so what's the high volume oil pump cost horse power wise? 10HP? 15HP? And at what RPM? 7500? I will never build another engine with a stock volume pump. Ever. Yall do what you want.
 
RustyRatRod said:
Ok, so what's the high volume oil pump cost horse power wise? 10HP? 15HP? And at what RPM? 7500? I will never build another engine with a stock volume pump. Ever. Yall do what you want.
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After the oil gets hot, I doubt if it`s very much. You all should find one of Bill ''crybaby'' Jenkins performance books and read it , he was a pretty darn smart dude !.
He just couldn`t handle the Sox-Martin hemi`s very well.

Pretty much feel the same way as RRR. I have run hi volume pumps on sbc`s, two hemi`s, and now this 440/505 -------
 
I can tell the difference on a cold engine pre-oiling with my cordless drill. Plus there were enough breakages or concerned over it that Mopar developed the heavier drive shaft for them. So yes, there will be power taken by the pump and to probably similar extent, the additional windage created by excessive oil draining back and flying off parts. Just my observations on the subject. I'm not going to worry about quantifying beyond that.
 
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