Thanks, 3100 but original block expired a long time ago, as Jim explained to me, the first thing they did to the motor was to bore them out to maximum (more hp. I suppose). The third owner short blocked it as that was the most ecconomical thing at the time.
The original block was eventualy sleaved back to standard & went into a HG Belmont. I have the reistration # of that car but it was deregistered before 1995. It was short blocked with a NK block which I am told is a very rare Bathurst replacement block for the CK ??