The best I know of is about 55LY - but this depends heavily on how you have the ship set up.
Farseer does FSD mods to level 5 - that's as good as it gets. What Farseer doesn't do, is L5 lightweight mods. Lightweight sensors are a good way to know a few tonnes off your mass, and get some more jump range. Remmeber, rolls are like slot machines, some are good, some are bad. If you get 48%+ optimised mass, it's a pretty good roll. If you managed to get bonuses that give you over 50% optimised mass, you're onto a God Roll™.
If you show us your loadout via
Coriolis shipyard or
ED shipyard, we can probably make suggestions.
Z...