Crankcase Vacuum System

Even the length and size of the tubing used in the catch can model for kart racing are critical.

Crankcase vacuum system.

In an internal combustion engine a crankcase ventilation system removes unwanted gases from the crankcase the system usually consists of a tube a one way valve and a vacuum source such as the intake manifold. If you run a dry sump system with a three stage pump one pressure stage two scavenge stages in most cases you cannot achieve a sufficient level 8 hg of crankcase vacuum to achieve that power gain. The extreme solution to prevent all of this is to install a vacuum pump that continuously draws the pressure out of the crankcase. While the design is very complex the operation is very simple to explain.

For most modest horsepower street engines however a vacuum pump. Moroso offers a lineup that includes both 3 and 4 vane vacuum. Crankcase pressure is evacuated via the valve cover and pumped to an external tank which vents the pressure and retains excess oil for periodic draining. Moroso is one of the most popular sources for these solutions.

The vacuum part of the pvc system provides the motive power for the flow of clean fresh air through the crankcase and into the inlet manifold via two routes taking with it the various crankcase emissions to be burned up during the combustion process. Our crankcase vacuum system is very complex in design and every hole groove passage and vent are critical to its successful operation. This provides a better piston ring seal less intake charge contamination and reduces oil leaks caused by high crankcase pressures while increasing engine performance. The unwanted gases called blow by are gases from the combustion chamber which have leaked and pass through the piston rings.

It s an engine performance trick practiced since the late 60s first with passive crankcase evacuation methods or so called pan evac systems. Designed primarily for drag race applications this crankcase evacuation system is designed to reduce pressure build up in the engine crankcase. This reher morrison big block chevy illustrates the simplicity of an external vacuum pump system. To get the pressure even lower into a state of vacuum another option is to employ a vacuum pump on your engine.