I fully understand the desire for more CRs, BUT that can depend upon how much more you want to spend on "more than 87 Pump Octane" fuels over the years.
Keeping the 2bbl means you want a "general use" engine that can burn anything and go anywhere, which is good. Not unlike the similar 383 2bbls. Which can mean keeping the CR under 9.2 or so, basically stock, in other words.
Looking for a performance increase, look to see if MAHLE has some "thin ring" piston/ring sets, which will probably be of a higher CR than stock. Add "plateau honing" in to the mix, too. End result . . . less piston ring friction drag = more power to the flywheel by itself. What happens with the CR is icing on the cake.
In getting the block machined, get it line honed and decked. That will put things at "blue-print specs", which can put the CR closer to advertised levels. From there, possibly just clean up the intake and exh ports for better flow. Maybe even using some David Vizard tricks in the process. OR add a pair of basic Edelbrock aluminum heads for their better combustion chamber and slightly smaller combustion chamber volume. Aiming more for better combustion dynamics.
Another piston option might be "quench dome pistons" (with the stock heads). Effectively makes an open chamber head into a now-more-desired closed chamber head.
With ANY aftermarket piston, find a digital scale and "Weight Match" the aftermarket pistons to OEM piston weights. Most aftermarket pistons are heavier than OEM numbers, by observation. This maintains the "factory balance" exactly without having to touch the crank or rods in that respect.
Enjoy!
CBODY67
