You don't need to add extra fans at all (they're only effective if the car isn't moving).

My current alloy core is 3" thick and the car runs @ 89 degrees always, including during track work.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]