mmm interesting... whats involved in going to 81mm ?
The machine shop in my town is good at general rebores etc and spend most of their time sorting out truck and tractor engines..
They put liners in quite regularly and have a large stock.
There is also a guy in Bangkok that makes custom headgaskets....

could use this piston ? from a mitsubishi...

81mm pistons with 82mm A15 crank makes it 1690cc
i have a spare block if it goes wrong.....

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