Hello all, I was wondering if someone can give me any insight into what I have observed about my car.. I have the M130 engine with the vacuum retard system. I measured the vacuum at the distributor vacuum port at idle and its only 5'' but if i measure at the banjo bolt fitting going to the tranny i get 15''..My symptoms are car pings when set I advance the timing a little but if i set timing to factory spec the tranny dont wanna shift right..My question is why the noticeable difference in vacuum between the two locations and does anyone think the car may run better if i tap into the banjo bolt for the increased vacuum..Cant seem to get this motor to run correctly..Any info or advice is greatly appreciated.

Set the timing where it should be and replace your transmissions vacuum modulator. Then it will shift correctly.

That is...... If it is shifting late or not at all.

This is a job that is so cheap it is best left to someone with the know-how since a tricky adjustment is required of the modulator when it is installed.