If you're getting correct natures, but incorrect IVs, that's probably just dumb luck or your syncronizer doing it. You should be able to just start the game with the info I gave you earlier, sweet scent, and get the IVs your after. Timer0 might be troublesome, but you should at least see correct IVs on occasion. If you're consistently not getting the right IVs, you might have made a mistake during calibration.