Stuck in traffic 340 got up to 220

I think the fact that Mopar performance engines were shipped with a clutch fan should say volumes about what fan to use, along with the shroud. These engines would run consistently around 180 degrees. Other factors to consider; timing, if it isn't right the engine will run hotter. Water pump, use a pump for an a/c equipped car, they will move more coolant through the system. Obviously this next thing shouldn't relate to your issue, but the whole cooling system should be flushed occasionally, to remove scale that will build up in the water passages. Back flushing would be the preferred method. Just a few things that popped into my head.