Something that I have noticed speaking of carbs is that the 440 for my Plymouth will run about 3 jets rich on the dyno from its fastest times. I figure it is from the sealed air scoop forcing air at the carb?
Your results are not uncommon
As the professor Warren Johnson has said many times, we don't race dyno, do we
I've learn to get the tune up close on the dyno and then finish tuning that motor in the car it will be raced in at the track it races on
I use the spark plug and time slips to help get me the best results at the track, when we have the time needed to get it done
