Changing Pistons

[RocketScott]

In the ongoing goat rope of an engine rebuild...

The pistons for my engine (CPL 1280) are no longer in production, neither Cummins nor aftermarket make them. I can find listings for them all over but nobody actually has them in stock. They were only used in the CPL 1256 and 1280, not a big market

Some alternatives have been suggested. The original pistons had a 15/1 compression ratio. One alternative piston would raise it to 15.5/1 and another would lower it to 14/1

All things being equal what would the trade offs be raising or lowering the compression ratio?

Going up to 15.5/1 doesn't seem like that big of a jump but I don't have enough understanding to know what else might need to change. The builder that made that suggestion said that I wouldn't need to change injector timing or pump settings. Keep everything else the same