IndyCar’s Future: The Evolution of the 2.4 V6 Hybrid Engine for 2028
The IndyCar series is stepping into a new chapter as it unveils its plans for the 2028 racing season. After more than ten years with the same technical framework, the series is embracing a significant evolution in its engine regulations. The introduction of the 2.4 V6 hybrid engine marks a carefully calculated shift rather than a complete overhaul, focusing on cost efficiency, durability, and maintaining manufacturer interest while ensuring high performance.
A New Era: Engine Specifications and Features
The new engine is set to be a 2.4-liter twin-turbo V6, which is slightly larger and more powerful than the current 2.2-liter engine that has been in use since 2012. However, this transition is far from radical; the aim is to enhance existing technologies without diving into costly and risky innovations that might not align with the current automotive landscape.
Similar to its predecessor, the new 2.4-liter engine will feature high-pressure direct fuel injection and will operate at revs exceeding 12,000 RPM. It will also include two larger mandatory turbochargers, managed by electronic wastegates, while preserving the foundational architecture that has been recognized and relied upon in previous designs. The performance gains are expected to come from improved refinement and overall efficiency rather than from a complete reinvention of the engine.
The performance targets are ambitious yet achievable. The goal is to achieve approximately 800 horsepower from the internal combustion engine, coupled with around 100 horsepower from the hybrid system, bringing the total output to about 900 horsepower. This figure represents an increase of nearly 100 horsepower compared to the current hybrid package set for 2025. Furthermore, there is a technical margin that could push this total closer to 950 horsepower throughout the 2030s.
Part of this performance boost does not solely stem from the increase in engine displacement; it also involves raising the turbo pressure limits. IndyCar is considering increasing the current limit of 1.5 bar (21.76 psi) to 1.6 bar (23.2 psi) for various track types, including road courses, urban circuits, and short ovals. This change would enhance power potential without necessitating more extreme engine designs.
The Rationale Behind Evolution, Not Revolution
You might wonder why the series is opting for an evolutionary approach instead of a revolutionary one. The answer lies in the quest for a solid return on investment (ROI). During the peak of IndyCar in the 1990s, manufacturers like Chevrolet, Ford, Honda, Mercedes-Benz, and Toyota poured vast sums into developing highly sophisticated engines, as the exposure and commercial impact justified such investments. Back then, V8 turbo engines of 2.65 liters could reach up to 1,000 horsepower but had short lifespans, often discarded after just one day of racing activities.
Today, the landscape has changed significantly. With NASCAR dominating the American racing scene and Formula 1 capturing global attention, IndyCar no longer delivers the same financial returns. Currently, each team utilizes the same engine for three to four races, with four units allocated per season, which reflects a shift in philosophy toward durability over extravagance.
Despite the leasing program allowing manufacturers to charge up to $1.45 million per car per season, both Chevrolet and Honda have operated at a loss. Moreover, no new manufacturers have entered the series in the past 13 years, highlighting a clear need for a reevaluation of the existing model.
While IndyCar strives to manage costs effectively, other racing series have successfully attracted manufacturers with more appealing solutions. For instance, Formula 1 has lured Audi, Cadillac, Ford, and Honda back to the fold starting in 2026 through a hybrid regulation that features high-tech appeal and a robust ROI. Similarly, series like IMSA and WEC have seen manufacturers willing to invest over $20 million per season due to the LMDh/Hypercar formula.
The takeaway is clear: when costs make sense, manufacturers are eager to participate.
Development of the 2.4 Engine: A Long Journey
The 2.4-liter engine did not emerge overnight. It was initially announced in 2018, with a debut planned for 2021. However, delays pushed this timeline back to 2022, then 2023, and ultimately led to a freeze on the project as IndyCar faced critical delays in implementing the hybrid system.
Both Chevrolet and Honda had developed and publicly tested the 2.4-liter engine in 2022 at the Indianapolis road course. They were prepared to compete in 2023, but the failure of the outsourced hybrid project necessitated a major shift. Consequently, both manufacturers took charge of hybrid system development at the end of 2022, redirecting resources originally allocated for the new engine. As a result, the reliable 2.2-liter engine continued its service.
With the hybrid system set to debut in June 2024, and the new chassis pushed to 2028, IndyCar decided to solidify the 2.4-liter engine concept as the cornerstone of its future regulations.
Although the 2.4 engine will visually resemble the 2.2, sharing the same basic dimensions and mounting points, it is a completely new design. Structural reinforcements have been implemented to reduce mechanical stress and lower reconstruction costs.
Mark Sibla, the Senior Vice President of Competition and Operations for IndyCar, summarizes the rationale effectively: “The 2.2 has reached an impressive level of performance, but it is completely at its limit. The 2.4 reduces the stress on the assembly, enhances durability, and also aids in controlling costs.”
The Approach to Standardization and Cost Management
During the regulatory development process, IndyCar seriously explored the idea of semi-standardized or even fully standardized engines. The logic was straightforward: reduce costs, facilitate the entry of new manufacturers, and avoid technological arms races. However, studies indicated that the potential savings were less substantial than anticipated, and there would still be opportunities for excessive spending in the limited areas that remained open for development.
The outcome was surprising: IndyCar opted for an approach that closely resembles a nearly fully customized engine, with only minor concessions made. Some components may be standardized, particularly those related to chassis installation, but the technical identity of each manufacturer will be preserved.
The true cost control measures will come from stringent homologation. Expensive components, such as cylinder heads, will have long validity cycles (three to five years), while simpler items could be updated more frequently. The goal is to prevent constant redesigns and the resulting escalation in investment.
“If the only open component were a screw, someone would spend $15 million trying to create the best screw possible,” Sibla explains.
Perhaps the most innovative conceptual shift is the potential use of Balance of Performance (BoP) not just as a competitive tool but as a financial one. IndyCar is considering incorporating torque sensors on the axles—a technology that is already being utilized discreetly—to accurately monitor engine performance.
If a manufacturer falls behind others in specific regimes, the series could offer small adjustments, such as varying turbo pressure in certain RPM ranges, without requiring that manufacturer to spend millions on recovery through research and development. This approach is not about making adjustments race by race, as seen in endurance racing, but about preventing disparities that could devastate budgets.
The Future of IndyCar
In summary, the 2.4 V6 hybrid engine for the 2028 IndyCar season represents more of a shift in mindset than a technological leap. The series has recognized that to ensure its survival and growth, it must deliver high performance, technical relevance, and controlled costs.
This pragmatic approach may mean less mechanical spectacle, but it promises greater sustainability and could pave the way for new manufacturers to emerge in the competitive landscape of IndyCar racing. As the series looks ahead, it aims to balance the excitement of racing with the realities of the modern automotive industry, ensuring its place in the motorsport world for years to come.
