Along with the F80 BMW M3 in Valencia Orange, a reader of our sister-magazine Bimmertoday spotted the F82 BMW M4 in Black Sapphire. The prototype features some limited camouflage, despite the official unveiling which took place last month.

The F82 M4 builds atop the new F32 4 Series Coupe while the F80 M3 uses the F30 chassis as the starting point. The M4 stands out with its sleek design and highly attractive roofline, and its balance proportions and low center of gravity.

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Since it starts on a smaller track (the F30), the F80 M3 has a width of 1877 mm versus 1870 mm for the M4, and furthermore, the rear-end features a wider bodykit to bring it to the same dimensions as the M4.

Both the BMW M3 Sedan and BMW M4 Coupe celebrate their public debut next week at the Detroit Auto Show, and coming in June on the German market. The price for the M3 sedan is at least 71,500 euros, the 23 kg lighter M4 Coupe is available from 72,200 euros. U.S. pricing will be announced next week as well, but in the UK the prices for the M3 sedan start at £56,175, while the M4 Coupe starts at £56,653.

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