I have heard good and bad against High flow water pumps, I have heard they actually can move the antfreeze too fast and you will still have an overheating condition. I just rebuilt the 355 in my jeep and have since finally got everything taken care of and it runs like a champ... the new cam is even more responsive
But i think This time, as it was built correctly the tolerances must be tighter then the original reman as with the same block its running warmer, 5-10* nothing has changed other then the lower end rebuild and the slightly larger cam... I pulled the thermostat right out and that seemed to take care of the overheating for now anyway.
Should I look into a high flow pump, or just opt right for an aluminum radiator? Obviously with the radiator I will be doing some Fab work...