Everyone says the vacuum advance should be hooked up to non ported vacuum . could any one show my a picture where they have hooked up their vacuum. Also the vacuum switch on the front left corner of a 1970 455 does this go into the manifold or is it just a mounting point? I am driving a 1970 electra 225 convertible. Thank You Tom ps I am using a late model Hei distributor with a msd module. :Comp:
The thermal vacuum switch at the front of the manifold screws into the water passage of the intake manifold. It is absolutely useless unless you are doing a concourse restoration and are looking for originality. Non ported vacuum is manifold vacuum. On the Q-jet, the nipple on the passenger top side is manifold vacuum. I like to run my vacuum advance off manifold vacuum. Stock, most Buicks from 70 and up used ported vacuum for the advance. Manifold vacuum to the distributor will give you extra advance at idle. The engine will run cooler at idle and low speed, your throttle response and cold engine operation will be improved.
