Carb tuning, larger accelerator pump nozzle?

You probably have too much emulsion for starters. If you have 4 emulsion blocks, you need to put emulsion in 1 and 3 and block 2 and 4. They don’t need to be any bigger than .029 and .026-.027 would probably be better.

So I’d go back to the 71 IAB, lower the Idle Feed Restricter to the bottom of the well and tune from there.

If it’s like most QF’s I’ve seen, you’ll also need to install T slot restricters.

That should give you a good starting point.