Tyre change throws Cup race open

NASCAR Sprint Cup teams face an unpredictable race on Sunday at Michigan after briefly testing the tyres they will race on, following Goodyear's call to change the left-side specification due to blistering issues. Many teams struggled to get the balance right during an additional practice session that NASCAR scheduled for Saturday afternoon in order to give competitors the chance to sample a harder left-side tyre.

Keith Greene Brian Hart Juan Pablo Montoya Peter de Klerk Cars Gimax