if you're serious, then tell me how much clearance inwards and outwards you get on your car sitting at the height you want with the suspension you have.
to do this, take your wheel off, get a straight piece of wood, drill two holes so that you can bolt it to two hub bolts, ziptie/stickytape a ruler to it perpendicular to the stick at roughly half the diameter of the wheel you wanna fit plus an inch to allow for tyres, then spin the wheel to see if the ruler hits anything. If the ruler doesn't hit anything, then measure the distance on the ruler. If it does hit something, then move the ruler and try again. This will give you the inner clearance from the hub (measurement a).
Then do the same, but keep the ruler at the highest point on the spin and take a measurement out to the fender. This is your outer clearance (measurement b).
Now:
a+b = your max rim width in mm
((a+b)/2) - b = offset in mm
This way you'll end up with the perfect offset or something close enough to what you need. All cars are different, as they'll run different suspensions at different heights.