Just to change the subject briefly away from EI, I'm about to perfect the cowl air intake openings which are approx 3.5".
I understand that the most efficient cooling results from the maximum pressure drop across the cooling fins so I'm wondering whether any of you have actually measured pressures in the engine compartment...top vs bottom. Is it too simplistic to say that the intake air velocity should be slowed down as much as possible before passing over the cooling fins and then accelerated out the ass end as best one can?

All of which leads to the burning question...no pun intended! Have any of you successfully reduced the diameter of the air intakes in an effort to lower drag? Seems to me that if I am going to make the effort to recess drag inducing Tinnerman washers on the cowl, I ought to at least consider other possibilities.

Angier Ames
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