My guess would be a Carter WCFB (white cast four barrel). They were the correct carb for the early 283. If memory serves me correct they flow 380 cfm, and have a weighted secondary air valve. They will only pull the air needed at wide open throttle. I had two 283's with this carb and they worked great. I also have a 56 chrysler with a 354 Hemi that runs the same carb. Works great there too.
John
