I am assuming you don't have vacuum advance since you have the old school points? I would give it more advance on the timingtry around 6-10, anytime you hop up an engine you should advance the timing, plus 4 degrees is pretty lean on the timing. After mechanical advance, weights in distributor, what is your total timing? I would aim for something near the 28-32 degrees total timing. Just be careful not to advance it too far as it will ping then. Is that quadrajet a vacuum or mechanical secondaries? Does the engine bog and then take off or just bog and not really feel alive all the way through rpm range? Personally on my old stuff I just use a vacuum gauge and timing light to tune my engine.