The Cartier Roadster, the Pirelli P Zero and the Parmigiani Fleurier Bugatti Type 370 have also been coveted among enthusiasts.

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Take a car like the Mustang Boss 302: 444 hp, limited-slip rear differential, race-tuned suspension and 9.5-inch-wide, 19-inch Pirelli P Zero tires.

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The front Pirelli P-Zero Nero tires chirp like magpies.

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Johnson is conducting a forum on Day Zero from 10 a.m. to 3 p.m. in San Francisco.

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