Converting 2.4 to 2.3
 

Is it possible/advisable to bore stock 84mm 2.4 cylinders out to 85mm in order to use them in a 2.3 short stroke motor?

(66 x 85 is required by rules of historic race series)

Also, could the 2.4 heads be used with the 85mm cylinders?

My starting point is a 2.4E (possibly 2.4S - haven't looked inside) spec motor.

you would be basically doing a .020 inch overbore (.5mm off the walls). That should be ok. The problem will be finding pistons to match.

-Andy

thanks andy - quite a few places sell 85mm pistons EBS etc

My Haynes manual shows a second oversize bore is up to 84.53mm. You'd be going bigger than that but not by much. I assume these are Biral cylinders? Just take a look at them and see how much iron will be left after the overbore.

-Andy