Using std numbers if you zero deck the pistons, 5cc valve pockets & a 90cc chamber volume you get 9.7 C/R the longer stroke of a 440 makes a higher compression ratio easier to obtain, but 9.7 without quench is likely gonna ping... If you leave to pistons .015 in the hole the C/R drops to 9.4 which likely is the ideal number without quench...

Now zero deck it, use a set of 84cc closed chamber heads & you'll be at 10.25 with good quench..