What engine Chevrolet uses in NASCAR

Chevrolet’s NASCAR Cup Series teams run the Chevrolet R07—currently in its R07.2 iteration—a purpose‑built, 358‑cubic‑inch (5.86‑liter) pushrod V8. Designed by General Motors specifically for NASCAR, the naturally aspirated, two‑valve engine is fuel‑injected and tuned to NASCAR’s horsepower targets, with engines prepared and leased by Hendrick Motorsports and ECR Engines to Chevy teams. In other NASCAR divisions, notably the Craftsman Truck Series, Chevy teams use the Ilmor 396 spec V8 that’s common across all manufacturers.

Inside the Chevrolet R07 Cup engine

Chevy’s R07 architecture debuted in 2007 to replace the older SB2 design, optimizing cooling, durability, and packaging for sustained high‑RPM oval racing. The current R07.2 spec reflects incremental updates approved by NASCAR while retaining the core small‑block V8 character.

Key specifications

The following points summarize the defining technical characteristics of Chevrolet’s NASCAR Cup engine as raced today.

• Displacement: 358 cu in (5.86 L), per NASCAR’s Cup limit
• Configuration: 90‑degree, pushrod (OHV) V8, two valves per cylinder
• Aspiration: Naturally aspirated; air limited by NASCAR‑mandated tapered spacer
• Fuel system: Electronic fuel injection with a standardized NASCAR ECU (McLaren Applied)
• Block and heads: Cast‑iron block with aluminum cylinder heads
• Lubrication: Dry‑sump system for high‑g loading and oil control
• Operating range: Sustained high RPM (commonly around 9,000+ in race trim)
• Output: NASCAR‑regulated—roughly 670 hp at most tracks and about 510 hp at superspeedways
• Timeline: Introduced in 2007; current iteration commonly referred to as R07.2; carried into the Next Gen era (since 2022)

Together, these features deliver the reliability and controllable power NASCAR requires, while preserving the traditional American pushrod V8 identity.

Who builds Chevrolet’s NASCAR engines

While the R07 is a GM design, Chevrolet teams source their engines from elite engine shops that develop, prepare, and lease the powerplants within NASCAR’s rules.

• Hendrick Motorsports (Hendrick Engine Department): Supplies engines to Hendrick and select Chevy partner teams.
• ECR Engines (Earnhardt Childress Racing): Supplies engines to Richard Childress Racing and multiple allied Chevrolet teams.

These builders iterate on reliability, drivability, and efficiency, extracting gains without breaching NASCAR’s tight technical box.

How NASCAR controls power and parity

NASCAR sets the framework that defines how much power engines can make and how they’re managed across different track types.

• Tapered spacers: Sized to target about 670 hp at most tracks and approximately 510 hp at superspeedways.
• Standardized electronics: A spec ECU and sensors govern fuel and ignition under tightly scrutineered maps.
• Uniform fuel: Sunoco Green E15 (15% ethanol) for Cup competition.
• Hardware rules: Pushrod valvetrain, cast‑iron blocks, and other constraints maintain cost control and competition parity.

The result is close competition where marginal gains come from efficiency, setup, and execution rather than raw horsepower escalation.

What Chevy uses in other NASCAR series

Outside the Cup Series, Chevrolet’s NASCAR programs encounter different engine regulations and supply models.

• Xfinity Series: Teams run 358‑cu‑in, pushrod V8s under Xfinity‑specific rules; Chevy teams typically use engines prepared by established builders, maintaining similar small‑block architecture.
• Craftsman Truck Series: Most teams, including Chevrolet entries, use the Ilmor 396 spec V8 (396 cu in/6.5 L), a common engine across all manufacturers to reduce costs and improve parity.
• ARCA Menards Series: Predominantly uses an Ilmor‑built spec V8 closely related to the Truck engine, again shared among brands.

These series emphasize cost containment and competitive balance, which is why spec engines play a larger role than in the Cup Series.

Brief history and evolution

Chevy’s R07 arrived in 2007 as a clean‑sheet NASCAR engine, replacing the SB2. It introduced revised bore spacing, improved coolant flow, and modernized internals suited for long green‑flag runs. NASCAR’s switch to electronic fuel injection in 2012 further refined control and drivability. When the Next Gen car debuted in 2022 with a new chassis, sequential gearbox, and other modern hardware, NASCAR retained the proven R07‑family V8s, with updates vetted through the sanctioning body.

Looking ahead

NASCAR and manufacturers, including Chevrolet, continue to study hybrid and electrified assist systems for future seasons, but as of 2025 no hybrid package is in race use. The Cup Series remains anchored by the R07.2 pushrod V8 under current regulations.

Summary

Chevrolet’s NASCAR Cup engine is the Chevrolet R07 (R07.2), a 358‑cu‑in, pushrod, naturally aspirated V8 designed by GM and built by Hendrick Motorsports and ECR Engines to NASCAR’s tightly controlled specs. In other divisions, notably the Truck and ARCA series, Chevy teams use Ilmor‑supplied spec V8s that are common across all manufacturers.