i ask for a thermo clutch for a HD cooling pakage on a 78 BB 440
then went to the JY and got a 7 blade fan from a amc hornet 6 cyl clutch fan set up
I also replaced the rad in the 85 truck with a 3 core HD cooling replacement rad..all brass no plastic
i have to bump the t stat up to 195 in winter to get a little heat
run a 180 in summer and it never goes over 190* in traffic
you can hear the fan cycle also when idling,takes a few mins and you hear it load up and roar blowing air on the engine side like it speeds up in rpms
few mins later it quites down and back to normal till the t stat opens again
I can watch the mech temp gauge move up and down with the fan
i also use a HD 5/8" shaft wp with 8 vanes with the non a/c pullys
the neck will have ribs down it instead of the gatlin gun holes around the shaft
if you have a/c pullys use a 6 vane wp
they will cavatate if an 8 vane is used with the smaller a/c pullys at higher rpms
a/c pully is samller and turns faster at idle to pump x amount of water with 6 vanes
non a/c pullys are bigger and turn slower with 8 vanes to pump same x amount of water at idle
match the correct parts and use new wp not a reman wp IMHO
