I would get the 7 blade fan & the other things mentioned: proper fan spacing in a tight fitting schroud/correct overdriven pulley ratio/high flow stat (not less than 180)/anti cav plate in the pump/adequate radiator/several drops of dawn liquid dish soap for a water wetter/some antifreeze/air directed thru not around radiator/MP clutch fan. ballpark timing & A/F ratio. EDIT coiled spring in lower hose. good regular Prestone green antifreeze changed somewhat regularly.