I'm planning on changing the cooling fan for the summer.  What sizes are other people using, the T-bird vendors seem to be selling 16 inch, but it seems that there is enough clearance for a larger fan and I want all the cooling I can get.

Thanks,
Don

here is the set-up I finally came up with - without using an electric fan.



As shown, there is a Hayden #2797 Severe Duty fan clutch, a cut down '68 Pontiac 7 blade fan (said to be off a GTO) and a reduced diameter aluminum waterpump pulley. The Hayden clutch is a "bolt-on" fits perfect, the fan had to be (very carefully) cut down to fit into the 18 inch opening - does not just fall on there but an easy fix with a bandsaw and careful layout. The small pulley is off a 289/302 and speeds up the waterpump - as well as offsetting the rpm loss of the clutch slippage (80%-90% speed engaged - 20%-30% dis-engaged). I've had my best luck - using the big block Chrysler sized thermostat and restricting the bypass hose.

 
 Steve Metzger       Tucson, Arizona

Back in the day I had a 6 blade fan and it still ran too hot. Once I went to an alternator I removed the 1 inch water pump spacer and after that it ran right at the thermostat.

  Vic Correnti

Hey Greenbird, what was the diameter of the pulley you used? There seems to be several different variations.