Hi Bob;
In Canada AFAIK all 83's had the B23E engine, but with a milder camshaft than the 81-82 with the K. The 84's got the B23F with dished pistons and about 9:1 CR. Stock early E's were 10:1 I think, and could be identified by the fender sticker advising 5 BTDC timing. The 83's went back to 12. Suprisingly enough, and like yours and Georges experiences, I am using the stock B21A breaker point distributor in my B23E, and it is set at 12 BTDC, and the thing doesn't ping at all. It pulls like a freight train. That distributor also used a vacuum retard, which I have left disconnected, while leaving the vacuum advance side connected. (push-pull unit on it) But I do use 94 exclusively.
High speed detonation is inaudible - past about 3500 RPM, and the damage it will do takes place whether we hear it or not.
Decarbonizing a B23 does help with the octane requirement - I decarbonized one for a customer way back in 1989 - although that engine had seen a lot of leaded fuels when it was new, and leaded fuel built carbon very quickly. A steady diet of unleaded makes decarbonizing a thing of the past.