On the Nordschleife the BMW M235i is faster then the MX-5 but has a higher PI, 205 to 194 for the Mazda, But I think it should be the other way around. Because the M235i is way faster then the Mazda and with this PI it starts from the back of the grid. The BMW also has a way lower weight to power ratio, the the Mazda Car HP weight kg/hp BMW 333 1425 4,279279279 Mazda 184 1140 6,195652174