Vacuum advance

RustyRatRod said
It also does something no one has mentioned. It gives you a certain amount of engine braking due to the vacuum falling off when you take your foot off the gas. That can make a difference in mileage right there.....and right now, gas ain't cheap. With it on manifold vacuum, when you lift your foot, vacuum goes up and pulls in total vacuum advance, and reduces that amount of engine breaking. It makes a very noticeable difference.

I agree completely, and thanks for bringing that up. I've always enjoyed taking my foot off of the gas and having the engine do a good bit of the braking. In fact, driving on the street like that *does* save wear and tear on the brakes and gets better economy. Brakes are such a waste of energy anyway! Thanks Rusty!