I'm 99% certain it will be the four blade fan you need. AC cars normally required 5,6, or 7 blades, a fan clutch, and a shroud. If others disagree, please feel free to correct my post.:idea2:
If you want that puppy to run cool.... put a 7 blade on there and dont worry about ''correctness''..... when it comes to cooling,,, too much aint enough.....:Brow:
I couldn't agree more. My '62 routinely ran 210-220* with the stock radiator and 4 blade fan in traffic. Go with a 7 blade clutch fan and it'll cool much better.
Not sure which is correct, but I would think the 4 blade as well. I know in the Uncles '66 GS that he races, it still has the four blade fixed fan in it. It does a great job at keeping the engine cool with the stock radiator. Last time we had it at the track, it was better than 90F out with the sun blazing down on the asphalt. He sat in the staging lane with the car running for better than 15-20 mins and it never got over 195F.
I replaced the 4 blade with a 18" 7 blade fan with thermostatic clutch, my car never runs over 190 in high summer, and doesnt rob power when I nail it. I'm with Doc - thats the first place to abandon originality.. you dont have to throw the old one away, you can always put it back on if for concours judging! Hey Doc!
I've heard kinda the opposite, but mine is the coolest motor I've got..never has reached 200 yet Granted - I grafted a 67 4 row core to my 65 side tanks, but it even ran cool with the original radiator. it's got a 180 thermostat in it.
The four blade is correct. It is the same as the one on mine. I'm Changing mine to a six blade for extra cooling. Go with the six blade....
I've heard the opposite as well. I've got a Jegs universal 2 core aluminum radiator with 1in tubes. When it's hot out (~90* and humid) it's not uncommon for it to run 200-205*. Under better conditions, it'll usually run 180-190*. And that's with a 160* thermostat. If I had to do it again I would have went with a radiator from Griffen or C&R.
X2, but my '66 425 non-AC engine came with a four-blade. As Doc said, "too much ain't enough". It now has AC, the AC water pump pulley (smaller) and a seven-blade clutch fan behind a new '82 Chevy pickup Diesel radiator. You can't make it overheat. You cannot overdo either cooling or battery. FWIW: I cannot remember having any major cooling issues with any of my many Nailheads which range from 264s to my .030 over 425. At one time or another I've had them all. I have always been a believer in having a good, clean radiator and cooling system. The only car that I have ever owned where cooling could sometimes be a problem was my '35 Chevy standard coupe. The radiator was old and a serious PIA to remove for cleaning or replacement, so I just lived with it.
I just installed the 5 blade approx. 20" fan. Car still runs hot after a while. Has the thicker A/C radiator and it was just cleaned and checked by the local radiator shop. I removed the condenser since the air is not hooked up anyway to allow better airflow. Stock shroud in place. Car is a 4 Speed. Advice? I do plan on a partial restification including getting the air working.
when is your thermostat opening?? maybe too low of a t-state and coolant isn't spending enough time in the radiator to cool. Paul Turbonailhead
Not sure what size is in the car. I may try to get a 180 and put put in a new one. Cheap thing to try. Thanks.
