A buddy of mine just picked up a 1979 F-250 with a 460 in it. It runs ok but runs very lean according to the plugs and has no power (0 - 50 in 10 seconds), along with running very hot. So far we have flushed the cooling system, replaced the thermostat (180*), changed from a 7 lb to a 13 lb radiator cap, adjusted the timing a bit, and replaced a heater hose that was kinked due to being routed incorrectly as far as we could tell. It now runs a bit smoother and the temp gauge reads about 3/4 of the way up the gauge on top of the "l" in normal.
We're gong to jet the carb up several sizes hopefully this week and see if that changes anything, but does anyone have any other thoughts or ideas on other things to check? Supposedly the motor has been rebuilt not too long ago and lots of stuff looks new (like the exhaust, which doesn't have a speck of rust on it), although the job seems to be only part done as nothing seems to have been tuned, and the coolant we drained out was brownish green and the dirtiest coolant Ive ever seen. Oh yeah, heres a picture