High Volume vs Standard Volume Oil Pump

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JGC403

JGC403

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I remember reading in a book published by Mopar that using a high volume oil pump with the stock size pick, won't flow anymore oil than the standard volume pump. So the engine is just wasting power turning the bigger pump. I haven't found any pickups that are bigger for small block pumps, so is it worth using a HV oil pump?
 
As far as i know there is no over size pickups for a stock pan AKA, K framed small block!
 
I've been led to believe in the last few years, that unless you have specific needs, a standard volume oil pump is more than enough for most street/strip apps.
 
I have a related question-

I have a 451 stroker that came with a Milodon deep sump pan and Melling HV pump. The pan hung down too low so I replaced it with a 933. Should I replace the HV pump with a standard one? Do I run the risk of running the pan dry with the HV pump?

Thanks!
 
txtopcat said:
I have a related question-

I have a 451 stroker that came with a Milodon deep sump pan and Melling HV pump. The pan hung down too low so I replaced it with a 933. Should I replace the HV pump with a standard one? Do I run the risk of running the pan dry with the HV pump?

Thanks!
Click to expand...

No.
 
if you use a HV you are going to need a larger pan with more volume, if the pump is HP that's pressure you are ok with a normal pan. HV pump, high RPM's will run out of oil at 7500 rpm's. Have it done before on my own vehicle and watch the info, it 100%
 
afaik some aftermarket pickups are thin wall compared to the stock one...so the area inside is bigger = more oil flow possible. The moroso pickup for the 8 quart pan should be thinwall for example, i use these parts.

I´m not a friend of the hv pump, if the engine is built to high performance specs there´s not that much internal leakage, a hv pump will create only heat and relieve the pressurized oil into the pan via the pressure relief valve. Most engines make good oil pressure with the stock pump - at least mine does.

Michael
 
If you are cranking the engine 7500 rpm...why in the hell do you have a stock pan on it?

So if I dont change the size of the internal oil galleries on my engine...how does a HV pump put more oil thru the same size gallery....more pressure yes...more volumn????
 
The pickup diameter becomes a restriction. It's not in most circumstances. The problem is the HV pump reaches that cavitiation point earlier. But - I think it's still way above the rpm range of most street cars. The real problem is with the block and the lower end clearances. If your clearances are tight, and the lifter bores are tight, and the passages in the block are stock size... The HV pump's output is far higher than the system's "leaks". Remember that pressure is the combination of volume and restriction. So the HV pump pushes a lot of oil through the bypass which adds heat to the oil and robs a bunch of power. IMO - that's how the oil pump drives get sheared... the resistance is so high, and internal resistance is less power to the crank.
To the OP - if the clearances are good and less than .0025 or so, you don't need an HV pump. However - the factory stock pump has a bypass relief spring that releases at about 50psi. You do want to make sure you've gott hat 10psi per 1000 rpm deal - so add the MP High Pressure relief spring or run the HP pump.
 
I have been running HV oil pumps with high pressure spring for over 25 years on street engines with no problems.
 
My 350hp 318 has a HV pump on it.

It pumps a ridiculous 65PSI through the motor at full noise.
Will be changing it back to stock before I go racing.
 
.............I mostly install the hv pump........and I have never sucked a stock pan low of oil even up to 6500....kim........
 
Run a std pump in my 590 HP 7300 RPM 360 solid roller motor. No problems here. IMO HV pumps aren't worth using, unless you're talking serious high RPM high HP race motors.
 
You can run 6-7 psi per 1000 rpm and be good if you want, its your choice.

One fact is the more you try to compress the oil by pushing more through the same lil galley, the more heat is created and viscocity gos away.
 
I stopped using hv pumps in any engine unless the customer wants it with no warranty what so ever. Because like other have said at high rpms you can run the engine out of oil in about 8 sec. And on the street no one shuts it down in 1320 feet so if you like to see how fast you can go you will get to do it once and then you can redo the oil system with your new engine. I have run an engine out of oil during the burn out which is about 4-5 seconds only in a stick car but i was driving someone else's car and we didn't know what was in the engine since then it has a stock pan and pick up and the engine has been in the car for 3 seasons now no problems. It is a brand x car but 10:1 - 10:2 at 121 -125 mph is not to bad. Just my opinion.
 
I've never owned a non-mopar and used to run HV pumps all the time. I raced on the highway over distance - never used a deep pan, or overfilled the stocker, and a couple engines had no windage tray and were maintaining 130mph and 5500rpm. I've never sucked a pan dry even with wide (worn) bearing clearances. There are literally tens of thousands of engines running the HV pumps and stock pans/pickups that get run hard for more than 10, 30, or 500 seconds. I have to wonder considering the numbers how much truth there is to "suck the pan dry". I don't buy it.
 
This is one way to get a bigger pickup. Its mainly for rear sump pans, but if you have the time and equipment, you might be able to make this system work for a center sump. Any size tube you can fit.
 

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I've seen a few pickups that were WAY too high in the sump on non-mopars...perhaps this sorta thing could attribute greatly to a HV pump sucking air at high rpm?
 
oldkimmer said:
.....................Well they need to put the blame somewhere............kim........
Click to expand...


Exactly.



Mike - I think if you hunt around there are several versions of that dating back to the 70s. Moroso made the one I'm thinking of - but it was listed for circle track use IIRC and I'm not sure it's even available anymore. You can also fabricate something into the cover if you really feel the need. But unless you're running large clearances and high sustained rpm with G loading - you won't need it. Modern lubrication systems revolve around oil control, not limitless volume. So perfect clearances (not just in the bearings), scrapers, drainback, and the right pan are what you should spend money on. At least in my opinion.
 
oldkimmer said:
.............I mostly install the hv pump........and I have never sucked a stock pan low of oil even up to 6500....kim........
Click to expand...

Yeah, we've talked about this before. I think we all pretty much agreed it was impossible.
 
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