Holley/Demon Carb stumble

WRT what @PRH was saying, you might find it interesting to compare with double pumper filmed on a dyno.
See Ryan Brown's first video here.
Ryan Brown Performance
He also has older video posted Video
I'm not sure how much he's doing now, but was certainly pretty good about sharing when video was just getting to the point it could be useful and posted on the internet. High speed film was (prob still is) just out of the question for most mortals but video has gotten pretty good.