273 4bbl, carb replacement?

I’m running into the same problem on my 65 Dart 273 on running alittle warm in traffic above 200 I’m running factory fan and shroud. I bought a new radiator as mine is original and little crusty. Check your timing also mine was at factory and I changed mine to what the guys here suggest 10-15 initial, engine runs way better even drivable when cold. I’ll keep you posted if new aluminum radiator helps my issue. Dustin