i doubt an engine dyno would give any real world info. setting up a performance curve with a vacuum advance isn't straight forward and seems to be specific to each engine/car/driving combo. i know i must've built more than 20 different combos, and still aren't perfectly satisfied with one engine combo. what works on one won't work on the other. i don't glean much from the magazine guys anymore. i do believe that the factory mopar distributor and factory vacuum units are the best to work with. finding usable springs and plates could be a challenge. the FBO plates i have are far from accurate. i don't think the general motors clone distributors are as flexible as factory mopar.