I REALLY need to get another video up. LOL.
My 4 barrel carb has two vacuum advance ports. Ported and Manifold. Ported allows the engine to idle at initial timing and Manifold vacuum allows the engine to idle at full vacuum advance. I believe I Did post a video on this thread showing the differences. I hooked the advance pump to Manifold advance and the idle rpm increased noticeably and the engine was Much smoother, but I did notice some hesitation coming off idle. Now that probably could have been fixed by retarding the timing a bit. Where I have the motor currently is 10 degrees initial with the advance pump hooked to Ported timing. No advance at idle, but full vacuum advance while cruising down the highway. I may try manifold advance again and retard the timing back to factory specs and see how it likes it, but so far it's been happy.