Are fan clutches only used on cars with AC?
Im trying to figure out if I go with them or just a bolt on fan.

 

Clutch fans and 6 or 7 blade fans are always found on A/C cars, and on some non A/C cars. They provide more airflow and better cooling.

 

If you ordered HD cooling on say a 1969 442 it would have had a clutch fan AND SHROUD. Shroud is the key word here, w/o that you are wasting your time and could actually make the cooling worse.

 

Another important distinction is that, when a fan clutch was installed by the factory, they also installed pulleys which overdrive the water pump, meaning the pump spins faster than the crank. Cars without a fan clutch used pulleys which underdrive the pump.

The reason for overdriving the pump is twofold: First, since these applications by definition needed more cooling, the engineers wanted to push more coolant through the engine. Second, at idle and low rpms, the fan spins slower with a clutch, so the engineers wanted to compensate and speed it up again.

 

You guys are amazing... is the shroud and rad the same for each type of fan?

 

Just getting back on to this, so what you're saying in that the bigger pulley (which is what i have) would be for a fan without clutch?

 

You need to know what you have now and what you should have. Like my 67 GS400 had a clutch fan, no shroud and AC pulleys on it when I bought it. It ran hot. I changed it to the right pulleys, a FOUR blade correct fan, no shroud and it runs perfect! If you say what combo you have (1970 Cutlass 350 w/o AC for ex.) Somebody here can tell you what it was or should be. Then...you go from there.

 

the engine is going into my 70 442, 455 w/o AC, w/ PS, unknown if i even have a shroud, engine was out of a car when i got it.


Some of my concerns/ questions are;

Im trying to get the correct setup for the car
-Do I need the clutch fan set up or just the bolt on and spacer?