340 running hot

I would run an 8 blade water pump and no smaller than a 18" fan if no shroud is used.
Despite the culprit..the 8 blade pump will not move too much but will move more at lower speeds than the 6 blade more efficiently cooling the engine....btw it won't matter if you run a 165 or185 stat....but I'm not into the 195 stats, higher average temp..
Things that help with "cooling system related" low speed cooling issues..are fan shrouds, bigger fans, water pumps with more blades...assuming the radiator is functioning and up to the task aka correctly sized. High speed issues "cooling system related", collapsing bottom hose, too small a radiator, fan belt slippage, clogged radiator tubes, bad head gasket or cap bla bla...you can search. Good luck!