Hello,
i ve just acquired and stripped this 1973 Thunderbolt registered a65 with a 72 engine and it has metal bottom conrods. unusually though, they have 4 tiny oil holes at the base of the conrod rather than the one on the drive side. i thought that 2 lhs conrods had been fitted but the conrods have 4 holes altogether spraying inwards and outwards from the crankshaft oil feed. it has the cast iron oil pump as well which i know was a later modification.
i ve never read about the conrod 4 hole modification in any A65 books i have.
the electrics are burn out and its been in storage for 40 years. but the bottom end is unworn after 44000 miles on the speedo, so the modification by Bsa may be an improvement?