Vacuum advance information and myths

Bewy said
RB,
Post #56. Using MVA at idle is one way to give the engine the idle timing it WANTS. There are other ways such as locked timing. The problem with locked timing is that the timing.....is locked. Nowhere to go if you get detonation. MVA is load sensitive & can be adjusted to keep out of detonation. That is the beauty of it & why smart people use it. And, no, you don't just plug the VA into a man vac port & walk away. This is where the tuning begins & forget if you are NOT using an adj vac adv unit. Idle timing is set up first, then the centri/dist curve. Not the other way around.

"The problem with locked timing is that the timing is locked and nowhere to go" but to detonate and no compensation. This is where i'm at. If you tune it the way you described instead of adding timing under acceleration and load where fuel quality decides if it pings you have the vacuum advance which actually reduces timing and eliminating the chance of ping as the timing goes away under load. My cars have never stumbled using this method. AND they run cooler this way. I also get beter mileage than the other guys IF they can keep their hot rods running.