IndyCar officially pulled the wraps off its next-gen race car, the Dallara IR-28, set to debut at the start of the 2028 season.
Developed in partnership with long-time chassis supplier Dallara, the IR-28 represents a comprehensive reset rather than a mere refresh of the long-serving DW12, promising more power, reduced weight, enhanced safety and closer wheel-to-wheel competition.
With initial shakedowns already completed by drivers Alexander Rossi and Álex Palou at Indianapolis Motor Speedway and the first oval testing underway this week, the new car is on track to break long-standing records and redefine the series for the next decade.
Here is everything you need to know about IndyCar‘s newest machine.
Powertrain revolution: 2.4-liter twin-turbo V6 and Helix hybrid system
At the heart of the IR-28 lies an enlarged 2.4-liter twin-turbo V6 engine supplied by Chevrolet and Honda, replacing the 2.2-liter units that have powered IndyCar throughout the DW12 era.
The bigger engine, now housed under a transparent engine cover, will deliver up to 760hp on road and street courses and 640hp on speedways, with the potential to reach 800hp in qualifying trim.
IR-28’s hybrid system, meanwhile, will feature a 100-hp (75kW) electric motor from Helix paired with a battery-based Energy Storage System (ESS), supplied by Bold Technology, with 14 times the energy storage capacity of the current system.
The Helix hybrid system remains mounted in the bellhousing between the engine and gearbox, but is 20 pounds lighter than its predecessor.
Xtrac transmission
Power from the hybrid V6 engine will be delivered to the rear wheels via a new six-speed sequential gearbox from Xtrac, IndyCar’s sole transmission supplier since 2000.
The new P1414 gearbox is 25 pounds lighter than the current P1101, helping shift the car’s weight distribution forward for improved stability and handling.
Cutting-edge aerodynamic design
One of the IR-28’s most significant advancements lies in its aerodynamic package, which has been completely redesigned to promote closer racing and reduce turbulent wake.
The sidepods are higher than those on the DW12, featuring a large undercut along the bottom edge that directs airflow over the top of the diffuser, further enhancing aerodynamic efficiency.
The new front wing is wider and features three elements with large endplates, mounted higher from the track surface to reduce sensitivity to car setup and running in another car’s wake. Speedway configurations maintain the two-element version of the same wing.
At the rear, the IR-28 sports a distinctive hoop-shaped wing assembly mounted above a new rear crash structure (attenuator). This design, reminiscent of the 2022-era Formula 1 rear wing, features a beam wing, endplates, and a three-element top wing that work together to reduce wake.
Perhaps the most innovative aerodynamic feature is the emphasis on underfloor downforce generation, with a long floor using a raised leading edge to create outward flow expansion and a large rear diffuser to produce the bulk of the car’s downforce.
To further manage tire wake and reduce outwash, the IR-28 introduces Tyre Wake Conditioners (TWCs) – boxed fairings positioned behind the front wheels and ahead of the rear wheels.
These devices pick up turbulent flow from the tires and direct it along the car’s bodywork, preventing it from expanding outward and disturbing the air for following cars.
Additionally, new rearview mirrors feature a more complex shape with a mirror pod and wraparound vane to manage airflow downstream along the car, improving visibility while reducing drag.
The safest monocoque in IndyCar history
Safety has been a paramount consideration in the IR-28’s design, with IndyCar describing it as the safest monocoque in the series’ history.
The survival cell features a wider cockpit with the aeroscreen now integrated into the monocoque along with a titanium halo for additional head protection.
The roll hoop and side-impact structures have been strengthened and made more efficient, with improved crash performance in all directions – front, side and rear.
Another notable upgrade is the introduction of electronically controlled adjustable anti-roll bars, replacing the manually adjusted knobs and handles. Drivers will be able to adjust sway bar settings directly from buttons on the steering wheel.
Driver cooling is managed through four dedicated inlets: two for general cockpit cooling (one in the lower sidepod and one on the keel under the chassis), one integrated inlet on the scuttle ahead of the aeroscreen, and a helmet cooling duct on the side of the aeroscreen.
Custom AXIS Inertance Control Suspension System
The IR-28 retains the pushrod-operated suspension layout with steel wishbones, but IndyCar has introduced single-supplier spec dampers for the first time in partnership with Custom AXIS, a division of Penske Racing Shocks.
Each car is built around a shared suspension called Custom AXIS Inertance Control Suspension System, scrapping open damper development in the series.
These dampers are restricted in terms of available settings depending on the track, reducing the enormous inventory of parts and development costs that teams have historically incurred.
Despite these restrictions, the spec dampers still allow the use of inerters (J-dampers), which have been banned in many other motorsports but are highly effective for controlling chassis motion.
Test schedule for new IndyCar Dallara IR-28
The IR-28’s testing program began in early August 2026 with shakedowns at Indianapolis Motor Speedway’s road course, driven by Alexander Rossi and Álex Palou.
The next phase of testing commenced mid September at the same venue. Additional testing is scheduled at Sebring International Raceway and other venues throughout the remainder of 2026 and into 2027.
Teams will not receive their IR-28 chassis until the end of the 2027 season, with the car’s race debut set for the start of the 2028 NTT IndyCar Series season.
