Story continues below this advertisement
Back in our June, 2011 issue, we showed you how much oil can accumulate in a late model intake plenum with Mopar’s factory blow-by vent system. It was shocking actually: within the plenum of the intake, clearly visible with the throttle body removed, was a pool of engine oil so large we dubbed it “Lake Petroleum.” A third to a half a quart of oil was sitting in there. Not good on so many levels; corruption of the intake air/fuel mixture, loss of horsepower, and contribution to engine-life-shortening deposits within the combustion chamber and on the valves.
There are a lot of air oil separators on the market today, commonly referred to as “catch cans.” They’re all basically the same, a large canister design with an inlet and outlet for the crankcase air flow and usually some steel wool inside. The idea is that crank air with oil suspended within hits the catch can and oil vapor falls out and settles to the bottom and clean air proceeds to the combustion chamber. We didn’t give much thought to the device we installed, we just bought the one that the shop with which we were working carried. It was a nice example of the breed, machined from aluminum with some thoughtful design touches.
But hold on, because a new design from Arrington Performance has come along that changes everything. We may not have put much thought into the air oil separator, but Arrington certainly has. The HEMI Air Oil Separator by Arrington Performance was actually engineered, not just put together. We know because we spoke with one of the engineers responsible for shaping its design and testing its effectiveness. And he’s not just any engineer. Mikah Barnett of All Angles Designs is a certified engineer and he works closely on a contract basis with Chrysler on some of its racing efforts and designs. Talking with Mikah is like wading into the really deep end of the automotive engineering pool.
Let’s look at how the Arrington device works and why we’re so enthusiastic about its design.