tie rods are a good guess, but if it didn't happen with his old rim/tire setup then that's probably not it.
Have them spun up and balanced, checked for bends, and do an alignment.
Hot: 2001 Estoril M Roadster
ZCP 19's, ZHP knob, JL 8W3
Cold: 2002 TiAg M3 6mt
ZCP 19's supersports, ZHP knob, UUC short shift GROM, OEM 18's w310's,
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