How about a middle of the road option? Like using a clutch fan. I've found this to be a great option as they are not nearly as noisy, saves on HP, and atfull tilt pull just as much if not more air than a straight fan. Been using them on my mopars for quite a while aswell as on a few fords. Not 100% sure when for actually started using clutch fans but i thought it was scarcely in '67.