Big Block Dart Cooling
I've heard the same thing on the housing. I'll be tearing down the motor's front end this summer so that may have to go in favor of another housing. A Flowcool pump will replace the 440 Source unit.
I also have a clutch fan with a multi blade fan. While the rad is out I'll take it in for a rodding and a good boil.
ding and a good boil. It's the original numbers matching rad so I need to take care of it.
The hard water down here is really hard on cooling systems. I may try using distilled water only with a good additive. Doesn't get cold here to warrant a heavy use of antifreeze.