[Barry_R]

A couple things to add/consider.

Much of the coolant management you see on professional race engines is related to preventing localized steam and air pockets as well as actual coolant flow.

The heads and upper cylinders carry a lot of combustion heat, and closed areas that don't circulate can cavitate into steam pockets. That is why you see added coolant passages in castings and external lines from intakes - coolant flow through them does not need to be high in volume - just has to be present.

The concept of reverse cooling has been applied to zillions of small blocks both in production and racing. The idea is to cool the hotter heads first and then travel through the block. I've never seen this applied to an FE, but there is no reason that it would not work.

The flow limitation in an FE is similar to most older engines - it's the circumferencial area of the open thermostat. You can get a startling amount of flow through a small opening. Some aftermarket FE intakes are darn near closed off in the front crossover and can benefit from a few minutes with the die grinder...