Boring out?

[spetz]

I have a 6A12 MIVEC (FTO V6) which is getting reconditioned.

I was wondering how safe is it to swap pistons from other engines?

In particular, this is what I am thinking
2.0L MIVEC pistons are 78.4mm bore
1.6 MIVEC pistons are 81mm bore
Now it is confirmed that they fit and it is ok to bore out the cylinders by 1.6mm
The question I have is, how will balancing go? And what about the stock conrods? They are getting shotpeened but would they have a lot more stress from heavier pistons?

Compression ratio will go from 10:1 to 11.5:1 (roughly)
The V6 MIVEC redline is 8100rpm and the 1.6 MIVEC is 8400rpm. Stroke of the V6 is 69mm and the 1.6 is 78mm

[Slaz]

Your engine machinist should be able to anwser all these questions but the piston weight wouldnt bother the rods it'd be the extra revs you intend on asking of this engine.

Other thing is the top of the piston and its valve relief's both the same? Dare say they will be being a mass produced item from OEM.

The other check would be the pin height and pin dia but assuming this has been checked to figure out your comp?

As for balancing this would be done like any other build.