Does anybody have any reliable information on how much clearance there should be between the radiator and the AC condenser? I think I heard someone mention that on overheating you should give more space between the two.
I have about 1/2" and have not had it on the road yet to get a good check on running temperature.
1/2" between is fine. The closer they are, the better the fan will pull air through both of them together. Too far apart and the condenser becomes an air block, creates turbulence in between, which reduces air flow.
My experience is opposite of Wayne's. I have the condenser right up against the radiator in my 53 sedan. It block air and runs hot. A local club member has a 41 Mercury sedan with stock flathead and AC. When he first built the car he had the condenser up near the radiator and his car ran hot. He moved the condenser several inches forward of the radiator and added an electric fan. The engine now runs cool.
Closely related. 55 f100, I would like to keep the cross-braces in the radiator horseshoe. If I mount the condenser to the cross-braces, I will have quite a bit more than the 3/16" space between that va recommends.
I've seen reference in other posts that some do install the condenser to the cross-braces... but I haven't seen any pros/cons. Cause over-heating, bad A/C function, clearance issues with grill, etc?
The reasoning behind the space is the fin spacing on the condenser and the radiator. If they happened to be the same (which they rarely are) you could put them closer together and align the fins. Since they do not have the same fin spacing, the air actually gets blocked if the condenser is mounted directly to the radiator.