273 4bbl, carb replacement?

That's the same build as my 66 Barracuda. What ignition are you running? What's your timing set at? You could gain some help on acceleration by increasing your timing. If it isn't advanced enough it could also run hot. I run a Pertronix Igniter II and my initial timing is set about 16*, with total timing at 36*. A rebuilt distributor also helped my idle.

When you say kinda hot in traffic, is that 200* or higher? Do you have a fan shroud?
It helps to have a hood to radiator seal and a hood to cowl seal for proper air flow.

'course it could still use a carb rebuild since it sat so long. I run a 1404 on mine and it's peppy and pulls good, especially at 3500 rpm and above!!