[Wbulk]

I am biased on this subject. I say if the car is driven on the street have a vacuum advance. On race cars vacuum advance has little value since they are running at full throttle much of the time where vacuum is low anyway. Vacuum advance on a street car has the advantage of improving mileage and can be used as an aid to improving idle on big cammed engines. Take for example an engine with a radical cam with a lot of duration and valve overlap. The idle can be a real problem, and for some you have to idle it at 1300 rpms or higher and sometimes get the throttle blades into the idle transfer circuit. However, if you have vacuum advance you can hook it to manifold vacuum, which gives more time to burn that un-burnt fuel and it greatly improves idle. I think it's a win win for cars driven on the street.