I have a Historic Rally Car running under pre 68 rules. It's a 1967 Sunny B10 (1000). I must use an A10 block but I can modify it intermally.

The problem with an A10 is the 3 bearing crank, any alternative crank is logically 5 bearing so not really an option.

I have heard a suggestion that there were some 3 bearing A12s. Can anyone confirm or deny such story?

Any other suggestions be enlarging capacity? Is 76mm about the maximum bore I should try for?

Mark

Hi mark and welcome to the forums. Read your introduction post and looks like you had some good experience in the rally game and development of your car.

For the A10 stroker questions I reckon you will probably get a good detailed response from the datsun1200 guys at datsun1200.com as there are quiet a few KB10 owners over there.