[Billy Nees]

Joe, there's a pretty big difference between the 2bbl that NHRA "accepts" on the 70 and the 71-72 2bbl. There's also major differences in the 70 and 72 engines if that's what you're looking at.
Give or take about a tenth one way or the other, you'll slow down a second.
Danny, the 2bbl that you had to use on the 283 is a small base 2g(same as my 307) and they're pretty horrible mainly because the top of the carb is so restricted. The 350s used a wide base 2g. There's one 283 stick Chevy II that did set a record with one though!