[patrickt]

Roger, most of us ignore the curb idle number and just check the total advance amount. Plug the vacuum advance, put a nice bright mark at 35 degrees and then rev the engine up to 3500 RPM, put your timing light on your mark and see how close you are to that bright line -- don't worry about the numbers. Then, through trial and error, try adjusting your timing in small increments (and not when the engine is revving at 3500, btw) to find the sweet spot that is before, on top of, or after that line -- and you do that by driving the car. Don't forget to hook your advance back up each time.