Look in the e53 section. Somebody did similar to your wish but they did go bigger diameter for off road.
I think the lug circles match gm 120mm or so the rims don't need to be from BMW possibly (though you may lose the hub centering).
The stock smaller rims on e53 are 17s. Tires are 235/65-17.
https://tiresize.com/calculator/
That site let's you find alternate sizes.
235/70-16 appears to be an exact match for 255/55-18. I don't know what the minimum wheel size will fit over the brake rotors but I've driven many miles on 235/65-17 and those are quite soft compared to the 255/55-18 the 235/70-16 might be all the balloon you need.
07-22-2021, 07:57 AM
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