Dimensionally, the new M3 Sedan is 4.6-inches longer, 0.4-inches wider, 0.1-inch higher and with a 1.8-inch longer wheelbase than the previous generation car. The new M4 Coupe is 4.6-inches longer, 0.7-inches wider, 0.4-inches higher and with a 1.8-inch longer wheelbase than the M4 that it replaces.
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