High pressure or high volume Oil Pump?

[AmadeusCharger500]

Which is better for mostly street use on a 440. Engine is rebuilt. Does anyone have a brand to reccomend?
Thanks

[71440charger]

if i am not mistaken it is both when you buy one it is  high pressure and you get more volume by porting the pick up to a 1/2 inch or cutting the pickup it self by the screen to make the opening  bigger it is kinda hard to explain unless you can see it done.

[andyf]

If it is a stock type rebuild then use a stock pump.  A high performance rebuild with larger clearances would use the hp oil pump.  The high volume pump has larger gears in it which pump the larger oil volume.  If you hold the two pumps side by side you'll see that the high volume one is taller to make room for the taller gears.

[firefighter3931]

A high volume pump is a high pressure pump by default.  The standard volume pump can be made to produce increased pressure by swapping out or shimming the pressure relief spring. Personally, i like lots of oil pressure in street driven engines....the more the better, especially at hot idle. 

Ron

[Mfr426]

I was told that these are high VOLUME pumps, NOT high pressure. It says volume on the Mancini page for the MP pump....

Check it out here...

http://store.yahoo.com/chucker54/mopper31.html

Just my 2 cents...

Mike R

[RD]

Melling makes HV pumps they are 63HV

Use a HV when using a larger oil pan on a performance oriented engine, use a stock pump in all other applications (i.e. stock pan, mild build etc.)  A stock oil pump will put out between 75-80 psi (dependent on type of oil).  How do I know?  My 34 year old stock oil pump on my 400 puts out 76 psi and its never been rebuilt.

[andyf]

high volume pumps can also be high pressure if you put the stiffer spring in them.  or they can be low pressure pumps with a soft spring in them.

volume is generated by the size of the gear teeth inside the pump.  pressure is regulated by the relief spring.

[firefighter3931]

  Andy, but all the HV pumps i've used have had the high pressure spring installed from the manufacturer. My 446 with .0025 clearance on the mains and rods has 80psi cold/60psi hot. I've installed them on tired engines in the past and seen dramatic increases in oil pressure as well.....kind of a "bandaid" deal for a worn bottom end, lol !

If you're going to use it on a high rpm engine, the hemi 6qt pan is good insurance. 

Ron