Yes, I have the 1.660” pistons.
Not sure of the kb 107 but maybe if the other “factory” used kb107 then the compression would be up around 10:1 instead of my 9:1.
I suspect when these engines were built by someone other than Cummins they used kb107 pistons with 10:1 compression and maybe more off the deck too.
None of which I am sure…yet.
