# BBS RS189 15x6 (?) ET38...question



## randomz (Jul 18, 2012)

OK, so recently grabbed a set of BBS RS189's for my e30 already bored to 57.1"

They measure 7.5" and 8.5" (outer edge, below lip to inner edge, below lip if that makes sense).

And don't worry, we still have our MKV :wave:

Been trying to figure out the specs on them and am having a tough time coming up with correct measurements. 

I'm told RS189 in stock form was 15x6 ET38 with 1" lip

Measured the lips while on the wheels (as seen here: http://forums.vwvortex.com/showthre...iece-wheels-lips-barrels-ect.&highlight=piece) and came up with:

Front 2" Lip (so +1...right?)
Rear 3" Lip (s +2...right?)

My question: what the hell ET do i have now with the new lips? and is that width correct? if there is an easier way to figure this out please point me in the right direction and i'll gladly learn!


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## 87vr6 (Jan 17, 2002)

If the wheel was 15x6 with a one inch lip, how does adding a two inch lip only make it 7.5... and the three incher only 8.5? 

I'm at work now, but I have a good calculator on my home computer for this type of thing. Did you measure the wheels properly? Get seperate measurements for the barrels and the lips... Recheck your math.

Rules of thumb:

Changing only the lip (and thus the width) will minus you 12-13mm for every inch of lip you add without changing the barrel...

15x6 et38 (4.5 barrel, .5 face, 1 lip) ---> 15x7 (4.5 barrel, .5 face, 2 lip) et 25

Same as above, but changing only the barrel 1" at a time makes the offset go up 12-13mm thus the 15x6 with 1" lip et38 becomes 15x7 with 1" lip et 50

Changing both is a whole nother ball game. I may be wrong about those measurements, someone else correct me, or at least until I get home and use the calc I have that works real nice...


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## randomz (Jul 18, 2012)

I must have meant 15x7 and 15x8, up too late last night

The barrels were not changed. Only the lips, so that makes sense. That was my understanding from reading around on here and other forums. 

So stock lip was 1", right? The lips are now 2" front (so +1") and 3" rear (so +2") rear, which would make them ET25 and ET14.

Ill gladly measure the barrels if that'll help, but can that be done without splitting the wheels?

Thanks a lot for your help man! Would deff be curious to see how that calculator works/what you come up with :thumbup:



87vr6 said:


> If the wheel was 15x6 with a one inch lip, how does adding a two inch lip only make it 7.5... and the three incher only 8.5?
> 
> I'm at work now, but I have a good calculator on my home computer for this type of thing. Did you measure the wheels properly? Get seperate measurements for the barrels and the lips... Recheck your math.
> 
> ...


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## randomz (Jul 18, 2012)

Bump...so the wheels deff measure 7.5" and 8.5"...so confused :banghead:


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