Every internal combustion engine has pressure & blow-by gases in the crankcase & valve cover. Some engines do a better job of separating the oil vapours before reaching the PCV (positive crankcase ventilation) vents than others. Most engines don’t, sending a poor mix of oil vapour & waste gases out the PCV vent & in to the intake system. These vapours smother important (& expensive) sensors with oil & gunk (typically carbon deposits). In worst case scenarios, this gunk can build up on the valves affecting performance. On a smaller, micro level, oil vapours take the space of oxygen molecules altering air-fuel ratios & lowering the efficiency and performance of your engine. 
The simple idea is to trap the oil vapours in the PCV system before they have the chance to affect the intake charge. As oil mist & gases enter a catch can they are forced to flow through a series of filter / baffle screens. As the gases flow through these baffles, oil & gunk run down the baffles to the bottom of the tank & lighter gases reach the outlet tube at the top and vent to atmosphere via a filter. Without these baffles, only a fraction of the liquids are trapped by the catch can. A drain in the bottom allows the tank to drain captured oil back to sump (or drained off at regular intervals via a valve) where the oil is reused and any deposits are captured via the oil filter.
The simple idea is to trap the oil vapours in the PCV system before they have the chance to affect the intake charge. As oil mist & gases enter a catch can they are forced to flow through a series of filter / baffle screens. As the gases flow through these baffles, oil & gunk run down the baffles to the bottom of the tank & lighter gases reach the outlet tube at the top and vent to atmosphere via a filter. Without these baffles, only a fraction of the liquids are trapped by the catch can. A drain in the bottom allows the tank to drain captured oil back to sump (or drained off at regular intervals via a valve) where the oil is reused and any deposits are captured via the oil filter.I hope this has been a useful blog for some one and if I can help in any way with your future custom modifying needs please contact us at www.flashcustoms.co.uk
Oil Catch Tank Design coming next
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