1969 Pontiac Firebird Runs rough

Engine Performance problem
1969 Pontiac Firebird V8 Two Wheel Drive Automatic

I have a 69 pontiac motor that has been rebuilt with HO heads, new radiator, hoses, t-stat, 2 to 3 year old water pump. It starts Ok, but try to drive off and it will stall, once you get past that, it drives ok untill it heats up, then it seems to get vapor lock, the clear inline filter will go completely empty, but still have 6pds pressure, If you loosen the clamp on the filter the line has pressure and gas will fill the filter, I replaced the carb, and that helped the start problems but the engine just seem too hot, Could the cam be wrong? Its a Reed cam 218/228. The radiator temp is 160 but at the t-stat we read 210? Could the headers, cam, and HO heads (10 to 1) all combine to heat up the engine too much?