I have ran several sets of the 6UL's, have them in 15x8 for my AS tires on the FiST, had 4 sets of ARC-8 from APEX for the M3 gonzo race car I was building...all very good wheels from very good companies, real enthusiast owners....
That said, the 6UL in 15" or the Avanti, Konig wheels are all made to the same quality and the price is much better. It is not a tough job to convert to 4x100, replacement stock rotors are easy to redrill to fit(no need to pay a machine shop as they are hub not lug centric). Have the hubs drilled or DIY, buy some APR studs, great low cost wheels are at the ready.
I did the conversion in the spring of 2014 with 283 miles on the car, first to do so as in quite a few firsts on this car, a very simple and low cost solution.
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BBK, ask FastBrakes to make the kit I talked to him about a few years ago, he has the data to do it and we talked about using a better rotor than the off the shelf WW kit like I used. I spent a considerable amount of time and money building my own front and rear BBKs to fit under 15" wheels and freely offered what I learned, data, etc to Brian, met with him, etc....
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Of course you can run 16x8 Dekagrams that should fit over the off the shelf BBK or 17's but not really a good wheel size for this car, 15 and 16 much better.
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