What’s new and what’s not in the 2028 IndyCar engines

While key features of IndyCar's new Dallara IR28 were revealed earlier this week, additional details have come to light regarding what's in development for 2028.

In a clarification provided this week, RACER has learned the new 2.4-liter twin-turbo V6s Chevrolet and Honda agreed to build for the car will have roots in the original 2.4s that were tested in 2022 and were meant to go live in 2023 before they were mothballed, although both brands have chosen to undertake significant redevelopment of those designs.

The existing 2.4-liter engine block could be the only significant carryover item from the first-generation 2.4s; Chevy and Honda have elected to invest considerable sums to redesign and alter almost every aspect of the motors. Those efforts are ongoing, which is what’s believed to have led the series to rely on a first-gen 2.4 engine to power the IR28 test mule during its anticipated runs over the weekend.

That motor is said to be an early Ilmor 2.4 made for its client Chevy, which the drivers chosen by Chevy and Honda would rely upon in the lone IR28 prototype chassis being readied for the first test. Once the second-generation 2.4s are ready, which are likely to feature all-new internals, heads and more, the next phase of testing can commence, but manufacturer testing with IR28s of their own is not expected to launch until 2027.

IndyCar and Dallara have opted to go with a spec electronics vendor for the IR28 as Cosworth, which serves as the spec supplier for the existing DW12 chassis, received the contract to outfit the new cars with its package of data and performance presentation and monitoring products.

The series also signed an extension with McLaren Technologie – known today as Motion Applied – to use its latest engine control unit (ECU), which maintains the precedent set with the DW12.

One aspect of the 2028 car will be seen in competition next year as IndyCar has chosen a spec wheel for the IR28 from Germany’s BBS. The decision eliminates Italy’s O.Z., which has been the most popular brand choice among teams with its magnesium wheels, and makes BBS the sole vendor approved to make and sell the new aluminum IndyCar wheels that should debut on the DW12 in 2027.

RACER will share more information about the next-generation IndyCar as additional details come to light.