[skyking]

Phil, if you see this I had some questions.
based on hutcho's diffuser graph, he talked about a maximum dimension for the total rise of the diffuser.
The trailer's problem is overhang aft of the axle, and dragging arse in certain driveway situations.
Proposed trailer diffuser is over 8' of length and needs to rise at least 7" to help with clearance. This is where TANSTAFFL kicks in.
1) 7" or more is a lot of air.
2) It has to come from somewhere. I see it filling in from the sides, and making a nasty double vortex bucket to drag around. Correct me if I am wrong.

I can make a moving diffuser with casters on it, that can "take care of itself" in those awkward situations. Would I make aero money if I reduced that rise, that angle?