Nowhere in the NHRA Rule Book does it mention carb boosters, only throttle and venturi sizes. Before the QF carbs were allowed, many 428 CJ Stockers ran Holley 3310 780s, or Boss 302/429 SCJ factory 780 Holleys, and passed NHRA teardowns. I set several NHRA National records in my 85 Mustang 5.0 in M & N Stock, and went thru NHRA teardowns 3 or 4 different times, and never once did I observe the Tech team measure a booster. And I did this with both the factory Holley/Motorcraft 4180, which has large, annular discharge boosters, as well as a universal 1850 600 vacuum secondary carb, with had regular boosters, and had the same sized venturis and throttle blades as the original carb. No mention was ever made about the boosters.