[RocktimusPryme]

Its not that electric fans move more air than big engine driven fans. Typically they dont. However, most people whose classic cars are set up even close to correct only have a problem at idle or stop and go traffic.

At these low RPMs, a good electric fan will still be giving its max air flow where the engine driven fan is limited by the low RPM of the engine. So if someone can get more air flow at the area where their vehicle actually needs it, AND save 10-12 HP by switching to electric. Its an easy choice.

I say this as someone with a clutch fan setup running cool. The pitfalls of the electric fan is that people cheap out on them and get units that arent sufficient at any RPM.