On Fri, 28 Dec 2007 08:27:28 -0500, "Eisboch" wrote:

Engine vacuum has been used for years for power brakes and on older car's
features like flip-up headlights and even the windshield wipers (on really
old cars).

Just reading through this, I now understand what you mean by vacuum
assist - I thought we were talking about a vacuum system like air
brakes.

My IH L-110 operated a ton of stuff off a vacuum pump - what a PITA.