We were one of the first to run vacuum pumps in B class. I use them all the time when the customer can afford to run them. Horsepower gains on a N/A engine we have seen as much as 40 depending on how much Vac. is being pulled on the crankcase. With my drag race engines I pull as much as 40 inches. ( such as Pro Stock)

help me out here .... one belt driven pump ...the motors are tied together via rear valve covers ... I see the pop-off valve on the starboard side of the valve covers then on the port side looks like regular breather ? ... Are we talking mega HP motors here or is there an advantage for 550-600hp ? m

In these pictures the pop-off valves are on the SP and PS VC. The vacuum contol valves (holds vacuum @ max level by leaking air) are on the SP and PP VC. As rigged, you only really need one of each valve.
In my experience/testing, there is no significant HP gain with a vacuum pump up to 6800 RPM with standard tension oil rings.
Why do it?...you wouldn't if +HP is your primary goal.

What do you think of using a 5 stage dry sump pump that pulls 10 - 11"@ 6,000... Piston sprayers to lubricate the walls and cool the bottom of the pistons, DLC coated wrist pins, Valve spring sprayers and Lifter sprayers ? Oil pan w/ Nascar screens on each pickup line and a valve on top of each valve cover, capped and shrouded w/ a Moroso screened cap ? The valve is to close with vacuum and open w/ 2 - 3 oz. of positive pressure. At RPM the valve closes as vacuum is introduced and @ low idle may open, subject to ring clearance. While one valve would suffice, two valves are thought to flow volume that should accommodate a burned piston. Thus, safe guarding against a pressurized explosion in the pan. The MILITARY SPEC valve is designed to be trouble free for an extended period of hours.

The oiling /vacuum system may also stabilize piston rock, scavenge oil causing, parasitic drag ,oil aeration and add horsepower. Oil pressure stabilization may also be improved.

i thought the engine required to be air tight to function ? i see youre running a breather , d oes this still work ? im no pro , just researched a little , and talked with rm builer on this subject recently im confussed ? does this pull air from one side an then exits through the pump? i thought you sealed complete engine incluing the dipstick witch losses vacumm .

also ive read to only pull 15 inches or less or could have oiling issues ? Do you run a vacumm Gauge on the dash to see / make sure youre vacumm stays below this amount very interested rigging looks good !!

If you are using a standard tension ring pack, decide how much you are spending on a vacuum system for maybe +5 HP. A dry sump oil pump system also adds little to no additional HP with a lot of cost. I think good oil control can be obtained with a well designed wet sump system for a lot less $$ at a 6000-6500 RPM max operating range.
What you are proposing/doing is top shelf...just expensive :D

Rob,
Those are not breathers...just look like ones. They are one-way "pop-off" pressure valves...only open if the system pressurizes/fails.

These pics show some of what I am talking about.

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