High Volume Oil Pump VS Standard Oil Pump

[jefflock]

I'm rebuilding my 340 right now and was wondering about changing the oil pump to high volume. I will be using the stock 5 qt pan. This will be mostly a street driven car but it will be abused on the strip also. Will a high volume pump run the pan dry? I have heard this can happen while making a 1/4 mile pass. Anyone with thoughts on this as I can use the advice. Thanks Jeff

 

[340mopar]

No it will not run your pan dry. The by-pass valve in the pump dumps right back into the pan if your motor uses less oil than the pump supplies. As long as your motor has the correct clearances it is a waste of energy and wear on the oil pump drive parts to run a HV pump. But lots of people run them and if it gives you piece of mind to run one then that is what you should do, after all it is your car.

I myself do not run them, not even in my drag cars.


Chuck

 

[9secSmallBlock]

If you run more than a half qt low on oil you will have a loss of oil pressure. I know this by first hand experience. My crate 360 I installed a HV pump on it and 5 qt pan. When it got about a half qt low on oil it would send oil pressure to 0 under hard acceleration btw shifting gears. Would come back up when I lightened up on accelerator though. To remedy this I do run about an extra 1/2 qt. IMO just stick with factory oil pump.

 

[388dart]

I'm rebuilding my 340 right now and was wondering about changing the oil pump to high volume. I will be using the stock 5 qt pan. This will be mostly a street driven car but it will be abused on the strip also. Will a high volume pump run the pan dry? I have heard this can happen while making a 1/4 mile pass. Anyone with thoughts on this as I can use the advice. Thanks Jeff

Standard will work just fine on a new re-build.

 

[ramcharger]

As long as you adhere to factory crank/rod bearing clearances, I don't believe that there is a need for a HV pump. The HV pumps used to be mandatory when running a large clearance strip engine. No one really builds that way anymore. The thinking used to be that the large clearance would reduce friction, adding HP on the top end.

I have heard that the bypass from a HV pump can aerate the oil as it shoots it back into the pan, but since I don't have a "clear oil pan" to confirm this nor am I small enough to hang out in there, I can't say for sure that it's true. I really don't think that having a HV pump will hurt anything, but as Chuck says, it's just a waste of energy.

If you're serious about the strip, baffle your stock pan with some sheet metal or get a baffled pan. Not having the pan baffled is most likely the cause of any oil pressure drop under acceleration.

 

[jefflock]

What about oil weight? 10w-30 vs 20w-50? My clearances will right about .003 my machinist tells me. Thank you guys for your earlier responses to my other concern.

 

[djwhog]

depends on the temp outside for a large part. I would think at least a 10-40 in the summer once it is broken in...

 

[ramcharger]

If your clearances are at .003, I would run the HV pump. Don't forget to install a hardened pump driveshaft too.

 

[perfacar]

hi, if you install fill groove mains, a std oil pump will be ok. we found that a hv pump will in fact run a stock 5 qt pan about dry at the end of the strip.
oil pressure will be very low. thia pan had baffles and windage tray installed.
15-40 rotella or mobil delvac 15-40 would be oil of choice with .003 clearance.
plus they have the correct additives needed for cam life. comp cams recommends rotella 15-40 oil for their cams.

 

[moper]

I run a std pump but with the HP spring from MP. You can also shim the stock spring. With the right clearances, oil pressure should peak around 65-70psi witht he std pump and HP spring. The HV pump moves a lot more oil, but as said, really takes a lot of power to run, and builds heat in the oil you dont want. The "sucking the pan dry" comes from hard launches and stock unbaffled small block pans, and HV pumps with poor oil drain back. If you have no windage corntrol, and you pump a ton of oil into the top, it has to get back somehow, and it has to go by the crank. So a ton of oil gets caught with the crank as it drains past. I smooth out drainback holes, and always run some sort of windage control. Then the stock pans are fine.