[Eljaro]

Bingo!
That was it. The MSD cable color coding is wrong in my case and thus the timing was out of phase.
I used an old distributor cap, drilled a large hole behind the #1 plug cable connector and watched the rotor with the timing light. The rotor tip was firing at the tail end instead of the lead. I did switch the cables, adjusted the distributor and all is well now. I connected everything as per MSD's instructions, but that apparently is no guarantee that everything will work 100% if they m,ess up with the cables and the phasing.
I wonder how many have the same problem and do not know. I have been driving around with a wrong phased distributor and only now have I discovered it.
Timing is steady now. Will try out the car tomorrow.
Thanks for the tip.