In its day, this 340hp with V12 engine was the top dog of sports-car racing (Carroll Shelby himself drove one).

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"You can see the drivers struggling after a few laps with the graining, especially on the soft compound, " said Giancarlo Fisichella, a 13-year F1 veteran who switched to sports-car racing in 2009.

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Unlike teams in some other big sports, those in stock-car racing see little of the broadcast revenues.

ECONOMIST: Motor racing