For the 2015 IndyCar Series season Dallara prepared their first facelift aero kits for the DW12 designed by them, in partnership with Wirth Research for Honda, and Pratt & Miller for Chevrolet. The original fourth generation Dallara IndyCar, the IR12, was introduced in 2012, when Dallara began providing the common monocoque and suspension parts for the new IndyCar formulae – known as the IndyCar Safety Cell – with the intent that the bodywork and aero parts can and will be provided by other manufacturers. 2011 Indianapolis 500 winner Dan Wheldon carried out the first official test of the Dallara IR12 chassis at Mid-Ohio in August 2011. Following Wheldon’s death at the season-ending race in Las Vegas, Dallara renamed the 2012 chassis the DW12 in his honor. The original IR12 (DW12) was later known as MkI, and was used for three seasons – in 2012-2014. The facelift version of DW12 was designated as MkII, and raced in the series another three seasons – in 2015-2017. In the first season of use, especially in its first half, the Chevrolet aerokits proved dominant, with Chevrolet powered teams winning 8 out of first 10 races of the season. Midway through the season, both manufacturers introduced an update to the aerokit with the Honda kit losing its front wing endplates on safety grounds, while Chevrolet introduced an additional winglet. The balance shifted in favor of Honda-powered cars (4 wins in last 6 races of the year).
In 2015 Takuma Sato drove the Honda-powered car in his 3rd season with A.J. Foyt Enterprises. The season for the Japanese driver was unsuccessful. Hi was only 14th in the final standings, and his only podium was 2nd place in the second race of Chevrolet Dual at Detroit Street Circuit.
|Takuma Sato||14||A. J. Foyt Enterprises|
|Dallara DW12 (IR12) Mk. II||Honda||ABC Supply|