Offset questions.

[phelixthecat]

First of all, how can I find the factory wheel offset for my 91 318i?
Second of all, even if I get wheels of a different width from factory wheels, keeping offset as close to factory as possible should prevent any adverse effects on handling, correct? Since scrub radius is measured to the center of the contact patch?

[LMC]

First of all, how can I find the factory wheel offset for my 91 318i?
Second of all, even if I get wheels of a different width from factory wheels, keeping offset as close to factory as possible should prevent any adverse effects on handling, correct? Since scrub radius is measured to the center of the contact patch?

I looked in the parts manual at the wheels....there is a little variation, but 5.5 x 14 and 6 x 14 factory steels and alloys for the E30 all show ET35. There's also a 6.5 x 14 with ET30 offset. So I'd say you're probably good with offsets in the 30-35mm range.

If OE BMW wheels are on the car now, the part number and size/offset for the wheel may be cast into the wheel, like:

36 11 1 125 688 6J X 14 ET35

(but looking at my factory wheels, I don't see them, so they may be on the back and require removal of the wheel to see)

[ObD]

www.realoem.com

Chose your model. Click Browse parts button. Choose wheels from the parts menu. Choose light alloy wheels. Choose your wheel. ET is offset.