Combined these give me a -46.5% mining module duration and capacitor bonus when simulating in Pyfa, which I think is the best you can get an Orca.
-46.5% cycle duration on your mining modules means the duration of the boosted mining modules is almost cut in half. The yield is increased by a factor 1/(1-0.465) = 1.869.
In other words, a 87% increase in yield. Not bad.
(67% was the old increase from before the mining changes end of 2021, if I recall correctly. It seems that got buffed when the subcapital industrial cores were introduced.)