Thanks for all the great replies, guys.
My AC core is mounted directly in front of the radiator and I'm using the tranny cooler that is built into the radiator. I am not using underdrive pulleys...GM stock original pieces. The shroud fits tight against the support, and the fan fits right into the shroud, just like it should. I have a thermal clutch, and the initial timing is set at 16 degrees. I have no idea what the total timing is...it's never been checked. I've played with the timing from one extreme to the other, but it didn't help the problem.
Sounds pretty good...I'd definitely need to upgrade my alternator to install one of these fans.
I don't have an anit-dieseling solenoid hooked up because I don't really need one. The VA Sanden compressor produces very little drag on the engine, so it only drops about 100 RPM when the compressor kicks on. Besides, the temp creeps up even with the AC off. The clutch also works well exactly as you described.
Now, to add another variable to the pot, this problem started right after I installed a new cam in the car. Before installing the new cam, the car would never come off of 180 degrees even if you parked it in drive 6 inches from a wall and left it for an hour. After I installed the CompCams XE268 cam, the temp problems started, but I don't understand why. The cam I replaced was almost the same cam...I had no idea what cam was in the car, and the one I installed was virtually the same cam. The engine idles at the same speed it did before the cam swap. I did not pull the heads or anything when I installed the cam, so I couldn't have obstructed a coolant passage. I only pulled the intake and water pump. What do you guys think???
The Club - GM Muscle Cars of the Carolinas
-1967 Camaro SS350 clone - 350/TH-350 with shift kit, CompCams XE268H, Dynomax Jet-Hot headers, Flowmaster American Thunder exhaust, Vintage Air
-2002 Impala LS - Medium Bronzemist Metallic, every option except engine block heater
<A HREF="http://www.furman.edu/~jtrauner" TARGET=_blank>Click here to see my Camaro and my parents' 2002 Impala LS.