Q: How Fast Should I Drive The Vacuum Pump For Best Results?
A: The optimum speed is 50% of the engine speed (2:1 Ratio). For low speed applications that run below 8200 RPM, running the pump at 66% of the engine speed (1.6:1 Ratio) works well. Moroso offers a full line of crankshaft and pump pulleys to accommodate these ratios.

Q: What Is The Best Way To Care For My New Moroso Vacuum Pump?
A: After the pump has been run for about 30 minutes, Moroso recommends that you disassemble the pump, clean all parts with carb/choke or brake cleaner and remove any carbon residue that may have accumulated during the break-in period. If the build-up of carbon is not removed, the vanes will tend to stick in their slots at low RPM - producing no vacuum at all.

Q: How Much Vacuum Is Enough?
A: Leading engine builders and race teams confirm that maxium power gains occur at 13'' to 15'' on a wet sump application using Moroso 710-22640 pump and over 20'' on a dry sump application using Moroso 710-22641 or 22642 pumps. Because dry sump systems promote great oil control in engines, more vacuum can be obtained with no effort to oil returning. In some cases excessive wrist pin and exhaust guide wear can occur if the proper precautions are not taken. Lower oil pressure readings are common with increased vacuum rates.

Q: Where Should I Plumb The Vacuum Pump To?
A: We recommend plumbing the inlet side of the pump to the front of a valve cover. This position is not only effective at creating maxium vacuum, but allows some oil mist to flow through the pump for increased lubrication and providing long-term performance. The outlet side of the pump should be plumbed to a breather catch-can that can be drained peridically. Do not plumb the outlet to your dry sump tank or into an exhaust collector.