[Bored&Stroked]

With a 3.217 bore and a 4" stroke (my assumption you're using a Merc stroke crank), the CI will be 260 cubes. As others have said, it will not make that much of a difference in the end - it is more important to have the right combination of parts that fit the chassis, vehicle weight, transmission, gearing and overall application. The most important aspects of the build should be compression, piston to cylinder head clearance (quench area), cam selection, intake manifold selection, ignition and exhaust. If you need any recommendations - just PM me or ask on this stie.

The good part of just a .030 overbore is that the block will have enough meat left for many more over-bores - assuming we all live long enough! LOL.

With that said, I tend to bore most of my engines to 3.312 (3 5/16) and run a 4" or 4 1/8" stroke crank - but I tend to go for more cubic inches as a goal.