HV oil pump vs Stock oil pan

-
If you're going to pull the pan to work on the pump, I'd go ahead and take a look at the rod and main bearing clearance while I was at it. It may be they have a bit more clearance than they should.
 
LOL... It's not going to suck the pan dry....
That would be like two quarts in each valve cover... LOL...
 
I've ran HV pumps on small blocks with stock pans and never had any issues. Years ago I built a 67 440HP and used a high pressure pump with the stock pan. The oil pressure oscillated until I added an extra quart of oil. When it was time to rebuild I replaced the HP oil pump with a HV and the oscillation issue went away with the normal oil level.
 
Last edited:
BTW 512, my stroker is an LA roller engine with factory magnum-style replacement roller lifters. I did some research as well and found the identical info you quoted from Mellings. As I mentioned, I increased the oil return volume by drilling additional holes in the oil filter adapter plate. Sure they want to sell oil pumps, but they conduct plenty of R&D as well.
 
I don't see an issue with hot idling at 17 psi in gear at idle, especially if "hot" means around 190 F
 
I believe that is a myth that the "HV pump will suck the pan dry". Someone debunked it a few years back, but I can't find the link....granted, I use a HV pump in my car with a 7qt pan, but only use 6 qts.
 
64 Sportfury said:
BTW 512, my stroker is an LA roller engine with factory magnum-style replacement roller lifters. I did some research as well and found the identical info you quoted from Mellings. As I mentioned, I increased the oil return volume by drilling additional holes in the oil filter adapter plate. Sure they want to sell oil pumps, but they conduct plenty of R&D as well.
Click to expand...

Please explain this as the filter doesn't return any oil.

The oil is pumped into the filter through those holes and out to the engine through the center fitting that the filter screws on to. It simply passes through the filter from the pump into the oil passages in the engine. You did increase the volume of oil available to the filter but one has to wonder if the outlet fitting is capable of flowing the extra oil. Not to mention the filter or the passages on the pump side.

I did the same mod to my adapter plate when I ran it. :thumbsup:
 
Last edited:
Here's a test for ya...
Take the oil pan off and cut out the top of both valve covers and cut the tops off of four quarts of oil. Have two buddies with two quarts each in their hands and have them simultaneously dump 2 quarts each in each valve cover and time how long it takes for it to start dropping out the bottom...:poke::popcorn:....:rolleyes:...
 
justinp61 said:
Please explain this as the filter doesn't return any oil.

The oil is pumped into the filter through those holes and out to the engine through the center fitting that the filter screws on to. It simply passes through the filter from the pump into the oil passages in the engine. You did increase the volume of oil available to the filter but one has to wonder if the outlet fitting is capable of flowing the extra oil. Not to mention the filter or the passages on the pump side.

I did the same mod to my adapter plate when I ran it. :thumbsup:
Click to expand...
Ok, I'm no oil system engineer. I read about the positive aspects of doing the mod and its working for me. Why then, did you do the mod?
 
64 Sportfury said:
Ok, I'm no oil system engineer. I read about the positive aspects of doing the mod and its working for me. Why then, did you do the mod?
Click to expand...

Not saying it doesn't help, but there a lot of factors to consider in a oiling system.
 
512Stroker said:
I have noticed in xtreme heat that the oil pressure on my LA 340 drops to 15-18 psi at idle while in gear. 10W-40 Dino oil, Wix filter
I am wanting to up the idle oil pressure via a high volume Melling oil pump M-72-HV.
Has anyone run a HV Melling pump with the stock 5 quart oil pan?
Ya hear the stories of "sucking the pan dry" with high volume oil pumps.
Keep in mind this engine is a street application with a rev limiter setting of 6500 rpm.
Click to expand...
Since u are installing yourself go ahead and spend the 30 to 45 mins and blueprint pump if details not on site look on utube !!
 
512Stroker said:
I have noticed in xtreme heat that the oil pressure on my LA 340 drops to 15-18 psi at idle while in gear. 10W-40 Dino oil, Wix filter
I am wanting to up the idle oil pressure via a high volume Melling oil pump M-72-HV.
Has anyone run a HV Melling pump with the stock 5 quart oil pan?
Ya hear the stories of "sucking the pan dry" with high volume oil pumps.
Keep in mind this engine is a street application with a rev limiter setting of 6500 rpm.
Click to expand...
I would not lose sleep over that idle oil pressure as the bearing loads are low. It is how the pressure responds as the RPM comes up a bit. 30 to 40 PSI at 2000RPM would be good.
 
RustyRatRod said:
If you want to add more pressure, the HV pump is not the way to do it. Get the MP high pressure spring and put it in the pump you have. But 15 PSI at 800 RPM hot is plenty. If you don't think it is, unscrew the filter while it's running.
Click to expand...
Oil pressure is a balance between pump volume and leakage out bearing clearances, lifters, rocker arms. The pressure relief spring is to limit the maximum pressure.
Now if the low oil pressure light is flickering in gear at idle but goes out as the revs come up, good chance on a high mile engine that the bearings are worn. Early overdrive equiped autos had this problem due to low oil flow at city road speeds. The factories went to slightly higher volume pumps to provide the low RPM pressure. Replacing the worn main and rod bearings fixes the problem. Those low oil pressure light switches usually ground about 5 PSI to turn the light on.
New engines are now built for the lighter weight oils and low RPM in mind for fuel economy and bearing life.
 
Dale Davies said:
I would not lose sleep over that idle oil pressure as the bearing loads are low. It is how the pressure responds as the RPM comes up a bit. 30 to 40 PSI at 2000RPM would be good.
Click to expand...

Only if you have a needle bearings on the rocker arms. 15 pounds at the gauge is probably close to zero at the rockers.
 
If you have 15 PSI HOT at 850 RPM idling, NO ISSUE!

The questions to ask is:
"What is the pressure at 2,500 RPM?" If its at 25+ PSI no issues.
"At 4,500 RPM?" 45+ PSI no issues.
"At 6,500 RPM?" If LESS than 65 PSI, then issues.
 
Dave_J said:
If you have 15 PSI HOT at 850 RPM idling, NO ISSUE!

The questions to ask is:
"What is the pressure at 2,500 RPM?" If its at 25+ PSI no issues.
"At 4,500 RPM?" 45+ PSI no issues.
"At 6,500 RPM?" If LESS than 65 PSI, then issues.
Click to expand...
I think I am OK through the mid range. If it would be making 65 psi at 6500 rpm it may barely get there. To play it safe I have the rev limiter set at 6200 rpm.
 
For the "WARM FUZZY"S" just go for it. It may rob 2 HP.

You may need to use a hammer and make a dent in the pan for the HV to fit. Some do and some do not hit.
 
i've used hv pumps in mopar, ford and chevy motors with stock sump pans and never had and issues. i'd fit it and maybe as mentioned change the oil for a 10/50, 15/50 or even 20/50 grade.
neil
 
Just a reminder, if going to a HV or HP pump it has been recommended you change the oil pump drive shaft to a hardened tip. Putting this HV pump in and going to a thicker oil has been know to twist the tip off old stock used shaft.
 
flyfish said:
I believe that is a myth that the "HV pump will suck the pan dry". Someone debunked it a few years back, but I can't find the link....granted, I use a HV pump in my car with a 7qt pan, but only use 6 qts.
Click to expand...
It "can" happen, but the small block Mopar is an engine it will never, ever happen to. Just look at the intake valley. There's no way in the world you'd pump the pan dry. Now, look at a Ford 351 Cleveland. Totally different story. If you're wondering, that is the front of the engine where the distributor is. This is in a mid engine Pantera. But nowhere for lots of oil to go very quickly.
CLEVELAND INTAKE VALLEY.jpg
 
cudamark said:
If you're going to pull the pan to work on the pump, I'd go ahead and take a look at the rod and main bearing clearance while I was at it. It may be they have a bit more clearance than they should.
Click to expand...
With only 15 psi at idle, the engine is leaking oil somewhere.
 
You must log in or register to reply here.
-

Back
Top