"I don't know but I've been told"
Demons are flow rated wet and Holleys are not. Some people say this accounts for the HP diff.
Within the error limits of the dyno, will the results be the same? Is it only the max cfm a carb will flow the only determining factor regarding how much power the carb will yield?
This is almost a loaded question, but a good one I think. 1st up, the Demon carb, depending on level of Demon carb, is a more adjustable carb. This adjustabilty allows you to dial in the fuel curve alot better than a standard Holley or Carter. Oe and general performance carbs need not be so adjustable for great performance. But if the fuel flow to the engine is a more refined and optioumized so it can make more power, it'll do so.
If the engine only needs 650 cfm, then swapping out to a 750 may very well not do much of anything on the big end. The actual real world drivabilt can suffer on a too large of a carb. So beware of dyno tests that make use of 750's on 318's.
There can be a muddy low end in the feel of the car. A 650 would serve you better in many ways at the expense of a few HP up top. You could very well end up being faster in the 1/4.
Why? The smaller carb will keep velocity up for better throttle response, atomize fuel better which in turn the engine will burn the fuel better for more power (Torque) down low on the RPM and help with the off the line take offs.
All the old time pros have said it is better to error on the side of smaller than suffer ill results under the bigger is better.
But I have never seen any "carb shootout" articles in any of the mopar mags I have.
You kind of have. Everytime they swap one out to look for more power. But your right I thikn, there hasn't been a direct carb to carb swap session on a single engine showcasing various carbs.
