Holley/Demon Carb stumble
FWIW Here's measurements from the primary side of a 3310-2 I bought a couple years ago.
and here's measurements from someone else, from a 3310-1:
and the restrictions in the -1 I have on long term loan is .033 IFR and .078 IAB. That matches what others have found so its probably unaltered in that respect.