I suspect that the additional air blowing directly under the sump is forcing unwanted heat from the muffler away from the engine and out the bottom. Since my CHT seem if anythng better, I would assume I have not effected the low pressure effect on the lower cowl.
I read an article a few years ago engine cooling and they talked about the lack of a low pressure at the cowling outlet impeding
the flow of cooling air thru the cowling. It seems that an injector tube using ram air to speed up the air flow at the cowling outlet
might work. Or a small air damto create low pressure at the cowling out let.
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