I have a 22" radiator which has just been recored with a 3 row high efficiency core, factory fan shroud, high flow 160 degree thermostat. On a nice cool 85 degree day the factory gauge will run about 1/3 and my laser says approx 170 degrees @ radiator top.
As for the same pulleys being used on the 383/440, as I read in my assembly manual, that when equipped with "High Capacity & Torq. Drv" see page 100 which shows the Hemi with a clutch fan and smaller pulley.
I assumed Torq Drv. meant clutch fan, am I wrong ?
Alan,
There are two (2) types of fan drives. A thermal drive clutch has a temperature sensing bi-metal element in the face of the clutch unit that senses the air temp and engages the fan independent of the drive speed. Hotter air temp permits the fan to operate longer and at a higher RPM to move more air. Conversely, lower sensed air temps has the opposite effect...allowing the fan to disengage sooner. A TORQUE DRIVE clutch functions on RPM only independent of temperature and limits the speed of the blades to pre-determined speed. The two drives resemble each other but operate entirely different manner. Which is better? A/C vehicles usually use the thermal drive due to higher sir flow temps while high performance applications usually use the Torque Drive to limit fan RPM and windage losses at high speeds. The pixes in this thread, show the Torque Drive unit and the A/C setup. My Mopar parts lists show the Hemi and RB Crankshaft sheaves the same single groove.
BOB RENTON
