I run a fairly well modified 250 in my 37 Chevy and run an electric fan. Clearance for a stock fan was a big issue as the 250 is slightly over 2 inches longer than the original 216 and also the fans location on the 250 put it at the bottom half of the radiator core where it would do the least good. I got a 14 inch electric from Parr Automotive in Oklahoma that is nice and slim and is very efficient. I also got a Painless fan relay and harness with a pre set 185 ON and 170 Off sensor that I mounted in the thermostat housing. The car has a Walker Cobra radiator and I run a 180 thermostat. The fan is mounted behind the radiator just below the top tank as a puller ( most effective way for these fans )and the engine runs 185 degrees all day long no matter the type of driving or how hot the ambient temp.
The fan is Parr's own brand and is a well made unit. I believe the fan was $70 and the Painless relay kit with the sensor was $60, 2 years ago.
Hope this sheds some light on using an electric fan.
Mike
