i don't know anything about 16" tires, but you need more rear tire. on my cup 2 (17x7 and 17x9) i used to run 235/255 toyo ra1 without any modifications (my fenders were rolled already though). i had also been able to run 205/255 MPSCs.
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Lane
'93 RS America | '03 M3 | '02 325iT | '98 328is | '15 i3 REX
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