SCCA® Solo classing — unofficial guide
What autocross class is a BMW Z4 M40i (G29)?
BSStreet
A stock 2020–2026 BMW Z4 M40i (G29) runs in BS (Street) under the 2026 SCCA Solo Rules.
From the 2026 rulebook (Appendix A)
Street: 'Z4 6 cyl (2020-26)' = BS; 4-cyl = CS.
Unofficial guidance verified against the 2026 SCCA® Solo® Rules — always confirm against the current rulebook before competing. Classing data cites the exact Appendix A wording it relies on.