Thoughts about oiling...

[green69rt]

I've never had a problem with the HV pump suckng the stock 4qt oil pan dry even at 7,000 rpm. Just me I guess.

A HV pump does not move one more drop of oil from the oil pan than a standard volume pump, at the same psi in the same motor at the same rpm.

Said differently, A HV pump with 70 psi at 7000 rpm is not pumping any more oil from the oil plan/to the motor, than a standard volume pump at 70 psi 7000 rpm in the same motor.

It is possible to pump an oil pan dry, but likely, it would not be because it has a HV pump

Can you explain it a little more...  I can be a little thick sometimes.  What does the HV pump do differently or is it just a marketing thing.

Let me take a shot from an engineering point of view.   An oil, positive displacement pump (like the pumps in our cars) will pump a certain "mass" of oil, at a given rpm, no matter what the pressure is.  If the "mass" can't make it thru the bearings ,etc. then it will lift the relief valve and send the excess back to the sump (edit, back to the pump suction.)  So the question is "will it go thru the bearings, etc?"  Maybe a small amount, the viscosity, clearance of the bearings and how "smooth" things flow have more influence than the pressure.  So why do it?   (check me out here guys..)  On high revving engines it takes more pressure to push the oil thru the crank and out to the rod bearings and the piston wrist pins because the of the mechanics (someone else explain, big lesson in mechanical,fluid dynamics.)  So, if you don't have a high revving engine and you are not putting a big load on your bearings, a HP/HV pump doesn't get you much except that you need to make sure your pump drive shaft is up to the job, because it will pump more oil thru the pump, but the extra will just cause the relief to flow more to the suction, almost no more will go to the engine.

Did I get it right??

[ws23rt]

  ^^ That's a pretty good explanation.   An addition I'd like to make is the extra effort the hv pump feels (that is not needed) costs fuel/hp and generates extra heat in the oil.

[68charger440]

So are you saying the HV pump is capable of more volume, but the restrictions within tbe engine prevent it from doing so except for extreme conditions?  I guess I should have paid more attention in physics class!  My head hurts.

[A383Wing]

you cannot compress a liquid.....stock pump and HV pump will push the exact same amount of oil through engine....the only difference is that if you open up all the oiling passages inside the engine to accommodate the HV's pump of pushing more oil

[green69rt]

you cannot compress a liquid.....stock pump and HV pump will push the exact same amount of oil through engine....the only difference is that if you open up all the oiling passages inside the engine to accommodate the HV's pump of pushing more oil

Yes, I think that's right.  If you take a existing engine and add a HP/HV pump to it you don't get much benefit.  You have to go thru the complete engine and change the various oil passages.  One of the main ones is the rod to crankshaft side clearance (edit, BSB67 corrected me, side clearance not so important as I thought.)

[68charger440]

you cannot compress a liquid.....stock pump and HV pump will push the exact same amount of oil through engine....the only difference is that if you open up all the oiling passages inside the engine to accommodate the HV's pump of pushing more oil

Now I'm confused again...In the first half of the sentence you say both "will push the exact same amount of oil" , then in the second you talk about "accomodating the HV's pushing more oil".  I'm not trying to be difficult, but is the HV pushing the same or more?  or are you confirming the statement below that I made back a couple of posts ago...
The HV pump is capable of more volume, but the restrictions within tbe engine prevent it from doing so except for extreme conditions?
Sorry to be so thick headed.

[BSB67]

Okay, some of the items stated are correct, but some not.

Go back and read my words very carefully, along with what I'm about to state.

The HV pump will pump more oil at the same pressure, BUT at 70 psi the relief valve is simply open more and recirculating the oil back to the to THE SUCTION OF THE PUMP (not back to the pan).  What will probably happen in the real world is if everything is equal, the standard pump will be at 70 psi, and the HV will probably be at 75 psi in the example that I gave earlier. 

I personally have never observed an application where the standard pump could not provide enough pressure ( i.e. volume) once the engine was off idle. Im sure that the condition could exist, but it would not be anything even near the realm of a stock-ish engine as we are discussing here.

The only time I have observed a possible need for a HV pump is in a very large bearing clearance motor, with full time valve gear oiling, and full groove bearings.  And even then, the only time there is a issue is at idle.  The long rotor pump (HV) pump will provide more volume and increase the idle oil pressure under this condition at idle.

The rod side clearance has something between little to nothing to do with oil pressure.

To the OP,  buying a new pan and pickup will be as big of a waste of $ as buying a HV oil pump for your application, IMO.

[A383Wing]

you cannot compress a liquid.....stock pump and HV pump will push the exact same amount of oil through engine....the only difference is that if you open up all the oiling passages inside the engine to accommodate the HV's pump of pushing more oil

Now I'm confused again...In the first half of the sentence you say both "will push the exact same amount of oil" , then in the second you talk about "accomodating the HV's pushing more oil".  I'm not trying to be difficult, but is the HV pushing the same or more?  or are you confirming the statement below that I made back a couple of posts ago...
The HV pump is capable of more volume, but the restrictions within tbe engine prevent it from doing so except for extreme conditions?
Sorry to be so thick headed.

both pumps will push the same amount of oil through an engine that has not been modified to take advantage of the HV pump moving more fluid, ie, opening up all the oil passages inside the engine to take the extra added oil from the HV pump...if you put the HV pump on a stock engine, you will not see any extra oil flow to any portion of the engine because the internal passages are still the stock size that the stock pump is more than capable of handling. It's like putting a 3/4" water hose on the end of a straw and seeing how much water comes through, it would be the same with a 1/2'" hose as well

And yes to the other post, putting a deep sump pan and pick-up on your engine is waste of $$ also...nothing gained but more money used to do an oil change...you have done nothing to the innards of the engine to warrant the big pan or extra oil. The only thing of concern is less ground clearance at the deep pan so you can poke a hole in the bottom and let all that oil out on the ground

[justcruisin]

It's about the restriction that is imposed on the pump, if the bearings have more clearance, more oil will flow. To maintain a certain pressure more volume is required for the larger clearance as opposed to a smaller clearance.

You can compare it to water - a fire pump is supplying water to a hose with a 1" nozzle and it must maintain 100 psi pressure at the nozzle to be effective. The nozzle is changed to 1 1/2" - the pump must supply more water to maintain the 100 psi.

An HV oil pump will maintain the pressure as bearing clearance is increased. At what point the standard pump will start to drop off

[myk]

IF I do buy a pan it'll be the stock replacement Hemi pan which is flush with the K frame.  I only want to have the extra capacity since I'm throwing the car around the roads a little harder than normal.  If you guys say I don't need to worry about the oil even during spirited driving then fine-that's more money for other 'mods like the Borgeson box that I want...

[68charger440]

Myk, sorry I turned your thread into a class on oil pumps and pressures.  I was just a bit confused like you and I never could take an answer that i didn't fully understand.  I think it works like I thought, it is just some explanations made it through my thick head while others didn't.

[chargd72]

An HV oil pump will maintain the pressure as bearing clearance is increased. At what point the standard pump will start to drop off

This it the million dollar question.  I've been following this thread daily as I'm doing oiling mods to my 360 block as we speak.  I've opened up almost all chambers from the pickup to the mains and round off all corners.  I also opened up my stock pump passages and cleaned up all sharp corners internal to the pump.  Will my stock pump hold up to the job?  Or is this the time an HV pump is NEEDED?

[Brass]

Anecdotally, I got the 7 qt. hemi pan and the HV pump because I had a small 4 qt. pan and wanted more pressure.  I drive my car a lot and I was not confident the oiling was sufficient because the (new, American made) lifters would complain after hours of running on the highway or after a few dyno pulls.  Now it holds 10 psi more than it did before at cruise, and there's no lifter noise whatsoever.  The stock pump was probably just fine but I suspect the small pan did not provide enough volume to circulate.  I'm happy with the upgrade.

[68charger440]

Yeah, I wouldn't worry about punching a hole in the oil pan because it sits a bit lower.  We're not the Duke boys anymore, although I did do some crazy stuff with mine back in the mid 70's   Now they are worth too much to get too crazy with them.

[justcruisin]

This it the million dollar question.  I've been following this thread daily as I'm doing oiling mods to my 360 block as we speak.  I've opened up almost all chambers from the pickup to the mains and round off all corners.  I also opened up my stock pump passages and cleaned up all sharp corners internal to the pump.  Will my stock pump hold up to the job?  Or is this the time an HV pump is NEEDED?



While opening up galleries and radiusing bends can be a good thing it is not the governing factor, the pressure and flow is relative to the smallest restriction, (with the relief valve setting the max) By cleaning the galleries etc you are increasing the flow potential by minimising friction loss - a bigger hose has less friction loss for a given flow than a smaller hose.

I am by no means an expert but my thoughts and experience is if your bearing clearances are around stock the standard pump will be OK.

[John_Kunkel]

The HV pump will pump more oil at the same pressure, BUT at 70 psi the relief valve is simply open more and recirculating the oil back to the to THE SUCTION OF THE PUMP (not back to the pan). 

And therein lies a problem; if you look at the size of the opening(s) in the relief valve you'll notice they aren't all that large. So, even with the relief valve wide open, there will be instances where the openings are too small to handle the excess volume and, with nowhere else to go, the pressure will build beyond what's practical.

[myk]

Myk, sorry I turned your thread into a class on oil pumps and pressures.  I was just a bit confused like you and I never could take an answer that i didn't fully understand.  I think it works like I thought, it is just some explanations made it through my thick head while others didn't.

Not at all man.  I don't know what happened to me and this car over the years but I have a phobia about....under-oiling.  I stare at my oil pressure gauge more than anything else when I'm driving lol.  Oil is life!   So anything I can learn about the subject is beneficial to me.  

Anecdotally, I got the 7 qt. hemi pan and the HV pump because I had a small 4 qt. pan and wanted more pressure.  I drive my car a lot and I was not confident the oiling was sufficient because the (new, American made) lifters would complain after hours of running on the highway or after a few dyno pulls.  Now it holds 10 psi more than it did before at cruise, and there's no lifter noise whatsoever.  The stock pump was probably just fine but I suspect the small pan did not provide enough volume to circulate.  I'm happy with the upgrade.

Theres a 7qt Hemi pan? 

[Brass]

I think it is the same one Ron linked to.  It holds 6 + 1 when using the large Wix filter.

[green69rt]

The HV pump will pump more oil at the same pressure, BUT at 70 psi the relief valve is simply open more and recirculating the oil back to the to THE SUCTION OF THE PUMP (not back to the pan).

And therein lies a problem; if you look at the size of the opening(s) in the relief valve you'll notice they aren't all that large. So, even with the relief valve wide open, there will be instances where the openings are too small to handle the excess volume and, with nowhere else to go, the pressure will build beyond what's practical.

Yeah John, it would be interesting to see actual flow tests of pumps under various conditions to see what's what.  Is there such a thing?  Till then we are just guessing, but somewhere I thought I saw that pump reliefs are sized to handle all possible conditions so who knows?

[BSB67]

The difference in the amount that the HV pump pumps relative to the std pump is proportional to the rotor length.  However, flow is immaterial in this discussion.

I have seen the HV pump go over 100 psi and buldge the filter.  Others have actually split the filter.  The relief valve has no idea what is downstream of the pump, and arguably contemplates that the motor has loose clearances and should not need to dump all the oil it has sucked from the pan through the relief valve.

[68charger440]

The HV pump will pump more oil at the same pressure, BUT at 70 psi the relief valve is simply open more and recirculating the oil back to the to THE SUCTION OF THE PUMP (not back to the pan).  What will probably happen in the real world is if everything is equal, the standard pump will be at 70 psi, and the HV will probably be at 75 psi in the example that I gave earlier. 

I think this explanation would have done it for me in the first place.  It covers the 'WHAT, WHY, and the HOW" of what goes on in a couple of sentences.  The others gave more color to the picture too, but I would have understood it from this.

[A383Wing]

Okay, some of the items stated are correct, but some not.

The HV pump will pump more oil at the same pressure, BUT at 70 psi the relief valve is simply open more and recirculating the oil back to the to THE SUCTION OF THE PUMP (not back to the pan).  What will probably happen in the real world is if everything is equal, the standard pump will be at 70 psi, and the HV will probably be at 75 psi in the example that I gave earlier. 

disagree, both pumps will push the same amount of oil through an engine that has not been modified to take advantage of the HV pump moving more fluid, ie, opening up all the oil passages inside the engine to take the extra added oil from the HV pump...if you put the HV pump on a stock engine, you will not see any extra oil flow to any portion of the engine because the internal passages are still the stock size that the stock pump is more than capable of handling.

[68charger440]

I think I got hung up on the same area as you.  Would you agree if his statement read "is capable of pumping more oil" instead of "will pump"? 

[A383Wing]

only if the internal passages were opened up to allow the more volume of the oil to be pumped through the engine....otherwise the HV pump is not doing any good on the engine

[BSB67]

only if the internal passages were opened up to allow the more volume of the oil to be pumped through the engine....otherwise the HV pump is not doing any good on the engine

You can certainly disagree, but you are still wrong.  It is a positive displacement pump, it will pump more oil, just not to the motor.  Go back and read carefully.