Quote:
The only real problem with this setup is that the little end of the A12 rods must be bored to take the larger wrist pin of the A15 pistons, which reduces their strength.

I ran A14 pistons in my 1200GX engine for an awfull lot of miles, first at the standard 76mm, then later at 76.5mm, with bored A12 rods. They never gave trouble, but i don't flog my engines like some do, & the possibility of rod failure was always something that i had in the back of my mind.

The right rod to use in a big bore 1200 block with either a12 crank & A14 pistons, or A14 crank & A15 pistons, come from the A12A engine.

I think that an A15 crank in an A12 block would be one of those projects that stoped being fun real fast.