There continues to be a lot of threads on overheating and I have had issues of my own with my 1985 carbureted 305 Camaro and my wife's 1987 TPI 350. I experimented with a variety of things and was never happy with the results. Both cars had all appropriate air dams, shrouds, and other cooling items installed but kept overheating (boiling over 220*, especially in the summer). Both had 180* thermostats installed. The 1985 had an oversize 4 core aftermarket radiator installed by me, but looking back on it I wouldn't waste the money on it again because it didn't help my cooling issues. I finally settled on the following to fix the overheating for good.

1985 carbureted 305 Camaro: I went back to the engine driven fan and mounted two small electric fans in front of the a/c condenser. I wired them to a 200* on, 190* off sensor in the coolant passage on top of the engine intake. At highway speed the electric fans don't run, but when it gets hot outside or I am sitting in traffic for a while the fan sensor trips the ground wire on the fan relay I installed and both small electric fans come on and bring it right back down. This fixed my overheating problems.

1987 350 TPI. It already had two factory original electric fans installed, but between the computer controlling one and the coolant sensor controlling the other it was always too cool or too hot with no happy in-between. I installed a Dakota Digital programmable controller (PAC-2750, $114) and set it up to kick one of them on around 195* and the second at about 205*. Overheating instantly fixed.