[beis]

not sure about the E-fan, haven't heard about it...I am looking to try the throttle body vs. spacer, but haven't heard much feedback yet and am still waiting to learn the mechanism of action that makes the engine more efficient.....you may laugh, but my mechanic and I took the stock air box out and drilled 1.5 inch holes on the sides that faced away from the engine and then replaced the stock filter...oh, and we did the spark plugs too, it made a modest improvement in gas mileage of about 1-2mpg on the highway....I drive 25 minutes on the interstate to work everyday which is basically my dodge testing ground for these kind of things, good luck