Friends;
Is it a design flaw in the head design that causes a poor heat transfer to the coolant, I see many flathead engines that have Ardun Heads, Offenhauser Heads and various supercharged flathead engines making a lot of horse power, the waste of which adds to the heat produced. Is this just a matter of corrosion? If it is a matter of corrosion proper flushing and coolant maintenance would greatly help the cooling performance.
In my case with an ohv engine in a 38 panel it is simple, I have no constraints, I installed an aluminum radiator that is shaped very much like the stock one but is worlds different internally, I have a much more efficient water pump, and I run a coolant as recommended by the radiator manufacturer. I can idle my engine at 1100 rpm, big cam, in this 97 degree weather for 2 hours and just sit there and watch my 30 amp electric fan switch on and off and my stat open and close, she cycles from 185 to 165 in the temp range.
I understand that my system is different than yours but I want you to be able to sit in a lawn chair with an umbrella on a 97 degree day with a nice cold beer or a lemonade and enjoy that sweet musical symphony of clicks and hums to your delight.
If there is a guy out there who could can park his flathead powered vehicle next to mine and join me for a beer or a lemonade and sit there under the umbrella on that 97 degree day listening to a duet of engines clicking humming and singing I would ask him to please share his system specs, his maintenance routine, his block cleaning purge and maintenance routine with the other guys here so they can enjoy life a little more.
I think it would be good to establish a base line of exactly what your block should flow at a minimum, what a good pump should flow, the radiator required and its condition, and shrouding. I realize that you have constraints, you want to keep your stuff stock, but if stock means cooking it thats not good, bend a little.
Maybe GM and Don could put their heads together and between these two very intelligent men they could put together a tech thread that can be referenced by a guy who is new to flattys, you could even put it on the hamb. Thank you, Frank
BTW, just acquired a Desoto hemi, it's a mess, can't even tell it's size for sure, so now I have a fun new puzzle to figure out.