Thor Schroeder: "Some cars, particularly late-models, have problems with too much oil circulating back into the induction tract, which leads to detonation and compromises efficient combustion. From the factory, excess crankcase vapors and residual oil are vented back into the intake manifold. Moroso offers an air-oil separator that can be plumbed into the PCV system to capture this oil mist. This reduces the potential for detonation and the formation of deposits on the intake tract and valves. It has a billet aluminum body that complements any engine compartment and can be polished, chromed, or powdercoated for a custom look. It also features a bottom drain with an elbow that makes draining the collected oil a mess-free proposition. The kit includes a stainless steel mounting bracket, inlet and outlet fittings, and plenty of rubber hose for plumbing it up."
Pressure and Volume
Mike Zeranski Jr.: "An engine's oil pressure and the volume of oil being pumped by the engine are related, but having a high volume of flow does not necessarily mean high pressure, and high pressure does not necessarily mean there is high volume. Stock engines built with tight clearances can achieve adequate pressure with standard-volume pumps. As the engine clearances are loosened, it takes a greater amount of oil to fill and properly lubricate the clearances between engine components. In these situations, standard-volume pumps may not flow the necessary volume of oil to achieve the desired pressure and a higher-volume pump will be needed. Since the pressure achieved at any given volume of flow will be dictated by the design of the engine, we usually leave pump choices up to the engine builder. If the pump chosen has the volume to match the design and clearances of the engine, then pressure should take care of itself."
Bob Sanders: "It's best to have the least amount of wasted energy in your oiling system. So really the only difference between a big-volume pump and a small-volume pump is the rpm at which the regulator opens. Most engines flow between 9 to 14 gallons per minute, so if you compare our smaller 875 pump to our bigger 1100 pump, the 875 might take around 2,500 rpm at the crank to get up to full pressure whereas the 1100 would be there by 1,800. There are dozens of variables in all this, among them engine tolerances."
Bob Sanders: "Stock oil pumps are great for the range they normally run at since maximum engine rpm is usually low. Single-feed gerotor and spur-gear style pumps are inherently prone to cavitation for different reasons. The single-feed gerotor-style pumps have deficiencies on the suction chamber filling, while spur-gear pumps suffer from oil trapped behind their teeth. When this happens, oil can't escape fast enough to keep it from forcing bubbles back into a liquid state. We try to fill the suction side of our pumps as smoothly and slowly as possible, as this helps to minimize the formation of bubbles. Then we squeeze the oil using a slow sine wave pulse by incorporating a dual-feed gerotor. This slower pulse rate performs much better at high rpm.