As mentioned before, I'm running the Old Aire Hurricane system in my 54 truck with a 7 pound cap and have experienced NO overheating problems or belching of coolant into my overflow tank. I'm running a new radiator from LMC (no special order), a 25-75 coolant mix with distilled water, 6 blade fan on an "early" 216-235 adaptor plate mounted pump, and I did add a 16" manually controlled pusher fan in front.
Only time I've had to kick on the fan was when I was the 9th vehicle in line at a fast food gas palace at shift-change time.
I'm not saying that you should NOT go with a system pressure increase but that with a decent fan/waterpump setup that it has been a non-issue with my truck. Keeping the engine temperature stabilized at thermostat temperature and avoiding pits and peaks will insure that you've minimized cylinder wall wear.
For those of you who are considering adding A/C to your truck, OldeAire offers a quality product and getting your cooling system properly set up will make "overheating" a none issue.
Dave
