Triple Step Lip BBS RS offset calculation

[lowgto]

Hey everyone!
Trying to make some wheels fit on my mk6 jetta
Theyre BBS RS 023. stock specs are 16x8 +24 5x112
I'm going to be triple slant lipping them to 18s
Trying to calculate width, offset, all that
Stock specs:
1.5" (38.1mm) lip
.5" (12.7mm) face
6" (152.4mm) barrel
SO with that bringing me to 8 +24 I'm trying to figure out my new specs but it looks like the offset is going to be way low.
I want to run a 4" lip in the rear, and hopefully 3" in the front, but its looking like thats not possible
6" barrel, 4" lip, .5" face = 10.5 -8.7 no? that won't fit
The fronts came out to 2.5" lip .5" face 6.5" barrel for 9.5 +16.7 or 9.5 +29.4 (I think the 16 will fit)
then 7" barrel, 3" lip, .5" face = 10.5 +16.7, fittable but not what I had hoped for. Am I doing some step in this calculation wrong? Do I need my backpads shaved?
Is there some way to make a 4" lip fit out back?

[Oh, Word?]

The calculations seem to be right or at least very close. You should go by the widths and offsets you want not by lip size. I've never seen the backing pad for that particular rs but chances are you won't be able to take more than 5-7mm safely. If you haven't seen people using that particular lip size and widths for what you want then there's gotta be a reason for it. Either stick with a build you know will work, build the wheels you want and the car around them or find yourself some different faces.

[Shaun708]

What widths are u trying to achieve?

[SilentHeaven]

Im in for this, my RS are on the way...

[SilentHeaven]

I think I will go ahead with 2.5" lips and 6” barrels all the way around. My faces are et17 and et33. I think these might work but I am going to double check before I buy. How did you get the numbers? I think I will just mount my faces and measure for the lip to make sure.