electric fan
#2
www.summitracing.com or www.jegs.com has the most popular ones. The best one I have seen is the Flex-a-Lite Black Magic Heavy Duty Electra-Fan. The part number for it at Jegs is 400-150 and it costs $184.99. Everything needed to install it is included if you have an aftermarket radiator like the Griffin or similar. I haven't installed one on a stock radiator.