High Or Low Volume Oil Pumps

[inou2]

Getting ready to assemble my engine. I've used several oil pump configurations, volume and bearing clearance wise, and had not had motor problems. Interested in any opinions!

[Bakas]

what's your motor combo? Ive always had high volume pumps, currently running a melling 10990 with a stock bbc pick up tube.

[XTEN]

inou2,I remember our engine guy saying something about taking a low volume pump,and making it put out less volume.He said theres no need for a high volume pump.(this,after I bought a high volume pump,of course).Ever hear of this?

[inou2]

Bakus, it's a .060 over 400, super victor, solid roller 630/630, 14.5 to 1, 850 Holley HP, Brodix track 1 heads, 2 inch headers, crank trigger.

XTEN, that's kind of what I've been doing on the last couple engines I've built, using a z-28 type pump with standard volume and higher pressure. My understanding is a high volume will leave too much oil on top, and cause spark scatter, too. Plus, you don't have to run the wider bearing clearances.

[chris1972]

Bakus, it's a .060 over 400, super victor, solid roller 630/630, 14.5 to 1, 850 Holley HP, Brodix track 1 heads, 2 inch headers, crank trigger.

XTEN, that's kind of what I've been doing on the last couple engines I've built, using a z-28 type pump with standard volume and higher pressure. My understanding is a high volume will leave too much oil on top, and cause spark scatter, too. Plus, you don't have to run the wider bearing clearances.

are you using the oil restrictor so that you don't get the oil to the top most will go to the mains and rods...little will got to the rockers...i never had spark scatter...only time i use stock volume is with a stock pan

[coppergmc]

What is the difference between race and stock bearing clearance? Are you talking about running clearances somewhere around .002 to .0025?

I'd use a Melling select pump.

[jameskirk57]

This is a topic I'm interested in as there is not a hard and fast rule as to clearances or at what level you *need* higher pressure or volume.

I run a stock volume and pressure pump. Think about it - once you get to the relief pressure (around 1300rpm in my case) you are wasting HP and adding heat recirculating oil through the pump at 45 (or higher) psi - the high volume pump really only makes a oil pressure difference at idle - I carry around 15~20psi of hot oil pressure at a 800ish rpm idle and have never had an issue.

[jameskirk57]

are you using the oil restrictor so that you don't get the oil to the top most will go to the mains and rods...little will got to the rockers...i never had spark scatter...only time i use stock volume is with a stock pan

x2 in your motor being all roller up top there is HP to be had with attention to the oiling system such as restrictors and standoffs in the block and a killer windage system

[wild572s10]

I also run 3 quart moroso oil accumulator to pre lube engine