Correct Sir, My statement/position is: "that mechanical adv will not alter rotor phasing" and that RP positioning is the relationship/clocking/distance between the rotor tip and the cap terminal when it fires which is checked by drilling the hole in the cap top and shining your timing light onto it just like you do down below on the dampener to check timing. My position: from idle to any RPM it will NOT move. I've observed it at least a dozen times in my work & again 2 days ago when I went out to my DD 85 Ramcharger & did it again & that dist has tight springs but I revved it up high enough so that I knew I was into some mech adv not sure how much & it did not budge. it shook a very slight bit cuz the bushings ain't dead on concentric but a moot point. Gentlemen place your bets (& actually that is just an expression as I'm sure online gambling is frowned upon) so we'll say that this is higher edumacation (Moparts Style) and the only question to be answered (which Trendz will likely answer for us next week (bless his heart) is WHO is the teacher and WHO is the student. Stay tuned for further episodes. RR. I want that steak! EDIT In the powerperformancenews video quoted above they state: "mechanical advance moves not only the position of the reluctor in relation to the pickup but also the rotor in relation to the distributor cap spark plug wire terminal" then (2) paragraphs down it says: "stock distributors align the rotor with the spark plug terminal on the distributor cap with the engine at the initial timing position and since the reluctor and the rotor are fixed together mechanical advance does not cause phasing issues because as the trigger is advanced so is the rotor". first statement is wrong and the second statement is correct. Trendz please hurry!