More air molecules find there way into the cylinder each stroke.
But it will also mean more regular air-filter clean-outs / replacements..
Cooler air also lessens the chances of detonation & knocking.
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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together". Dwight D.Eisenhower.