[mr0077]

One of the best and easiest improvements you might try is to seal around the edges of the fan shroud to prevent air from leaking out instead of going through the radiator. That one change on my last 460-powered Cobra solved the problem, and I only had about a half-inch gap.

FWIW, the T-stat only determines the opening temperature...IMHO, a 180 is better for a FE than a 160, particularly in the winter. The T-stat lets the engine warm up to target temp faster, then opens and tries to maintain opening temp as a minimum temp. If engine wants to run hotter than T-stat opening temp, putting in a T-stat that opens at a lower temp won't help control temp, and taking it out may make things worse, because another function of the T-stat is as a restrictor, so flow through the block is somewhat pressurized, to help minimize steam pockets and hot spots.