Thanks, Glenn and Dr. Dan. See, I read that page 00-0/21 (the lower row) to mean at idle without any load.
I will soon be checking my valve adjustment, and at that time I will also check out the cam timing. I'm fairly confident that it is spot on, but the injection pump timing was done several years ago, so it remains a question.
Another thing I need to check is whether I have too much exhaust back pressure.
Oh.... per Dr. Dan's suggestion I advanced the timing to 5 Deg. BTDC (with vacuum); I have no pinging.
What would you say about me advancing another 3-5 Deg.?I just posted on another forum.....asking if anyone knows the MB specification for engine vacuum at idle for my car. No response from them yet. They will probably refer me back to you guys.
Thanks to everyone......