Sounds like cheap protection. Thanks for the info. Never used them on my 2003 Cobra, is this more of an issue with the Shelby's?Excess oil blow off from the valve covers get pushed back in the supercharger. This can cover the internals of the supercharger and lower the octane of your fuel when they mix. Lower octane can lead to detonation if it goes down enough, especially when it get cooler outside. Oil separators prevent this potential problem. Passenger side puts out 90% of the oil to the supercharger so that side is the most important. I have one on both sides of the engine. Yes, I sleep better at night ;-)