What Kind of Engine Do NASCARs Have?

NASCAR Cup Series cars run naturally aspirated, pushrod V8 engines with a maximum displacement of 358 cubic inches (5.86 liters). Built by Chevrolet, Ford, and Toyota, these iron-block, aluminum-head engines use electronic fuel injection and Sunoco Green E15 fuel, producing roughly 650–700 horsepower at most tracks and about 510 horsepower at superspeedways due to intake and aerodynamic restrictions.

The Engine at a Glance

The core specifications of a modern NASCAR Cup Series engine reflect a balance of tradition, parity, and performance. Below are the defining characteristics that set these powerplants apart from typical road-car engines and many other top-tier racing series.

• Architecture: 90-degree, pushrod (OHV) V8 with a single cam-in-block and two valves per cylinder
• Displacement: Up to 358 cu in (5.86 L), a long-standing NASCAR limit
• Induction: Naturally aspirated (no turbocharging or supercharging)
• Fuel: Sunoco Green E15 (gasoline blended with 15% ethanol)
• Fuel Delivery: Electronic fuel injection (introduced in Cup in 2012), managed by a standardized ECU
• Materials: Cast-iron engine blocks with aluminum cylinder heads
• Output: Approximately 650–700 hp at most tracks; ~510 hp at Daytona, Talladega, and Atlanta due to rules
• Rev Range: Typically up to about 9,000 rpm, track and setup dependent
• Lubrication: Dry-sump oiling for reliability under sustained high lateral loads
• Suppliers: Manufacturer-specific designs from Chevrolet (R07), Ford (FR9), and Toyota (TRD V8)

Together, these attributes produce the distinctive power curve, responsiveness, and sound that define NASCAR racing, while ensuring reliability over long green-flag runs and hot, high-load conditions.

Who Builds Them, and What’s Common vs. Brand-Specific

While NASCAR mandates key parameters for parity, each OEM develops its own engine within those rules. Here is how the major suppliers differ within a tightly controlled framework.

• Chevrolet: R07 small-block V8 designed specifically for NASCAR competition
• Ford: FR9 V8, a clean-sheet NASCAR race engine emphasizing cooling and reliability
• Toyota: TRD Cup V8, engineered by Toyota Racing Development for durability and top-end power

Despite unique architectures and development paths, all three are constrained by the same displacement cap, valvetrain layout, fuel, and ECU standards, keeping performance closely matched across the field.

How NASCAR Controls Power and Parity

NASCAR manages speeds and competition through technical regulations rather than outright engine bans. The series uses airflow restrictions and aero packages to tune horsepower and race dynamics by track type.

• Horsepower packages: Approximately 670 hp for most oval tracks and road courses; roughly 510 hp at superspeedways (Daytona, Talladega, Atlanta)
• Airflow restrictions: Tapered spacers and intake rules limit peak output and top speed
• Aero/gear frameworks: Track-specific aerodynamic configurations and gearing complement engine rules to control overall performance

This approach preserves the character of NASCAR’s V8 engines while managing speed and keeping competition tight across different venues.

Do Other NASCAR Series Use the Same Engines?

NASCAR’s three national series share common DNA in their powertrains, but with series-specific rules that tailor performance, cost, and durability to each level.

• Cup Series: 358 cu in, naturally aspirated pushrod V8s with EFI and standardized ECU
• Xfinity Series: Naturally aspirated pushrod V8s of similar displacement, governed by series-specific intake and technical limits
• Craftsman Truck Series: Naturally aspirated pushrod V8s with rules adjusted for the truck platform and race formats

While the exact hardware and limits vary, all three series maintain the hallmark American small-block, pushrod V8 formula that defines NASCAR’s sound and spectacle.

Why NASCAR Sticks With Pushrod V8s

The persistence of OHV V8 engines is not accidental; it’s central to NASCAR’s identity and competitive model. Several factors explain the choice.

• Parity and rules stability: Tight specs make it easier to regulate performance and costs
• Durability: Robust designs survive long races, heat, and bumper-to-bumper traffic
• Culture and fan appeal: The sound and throttle response are integral to NASCAR’s brand
• Cost control: Familiar architectures help teams manage budgets and logistics

These considerations, together with manufacturer investment in proven platforms, keep the pushrod V8 at the heart of the sport.

What About Hybrids or Alternative Powertrains?

As of the 2025 season, no hybrid systems are used in NASCAR Cup Series points races. NASCAR has tested and publicly demonstrated alternative technologies—most notably unveiling an electric demonstrator in 2024 as part of a sustainability roadmap—while continuing to race on E15 gasoline to reduce lifecycle emissions compared with pure gasoline.

Any future hybridization would aim to retain the V8 character while introducing energy recovery for efficiency and performance at select venues. For now, the competition engine remains a naturally aspirated 358 cu in V8.

Summary

NASCAR Cup cars use naturally aspirated, 358 cu in (5.86 L) pushrod V8 engines with EFI, iron blocks, and aluminum heads, producing about 650–700 hp on most tracks and ~510 hp at superspeedways. Built by Chevrolet, Ford, and Toyota within strict rules, these engines prioritize parity, durability, and the signature NASCAR sound—while running on Sunoco Green E15 as the sport explores broader sustainability initiatives.

What engines do Nascars use now?

EFI V8 engines
The cars are currently powered by EFI V8 engines, since 2012, after 62 years using carburetion as engine fuel feed with compacted graphite iron blocks and pushrod valvetrains actuating two-valves per cylinder, and are limited to a 358 cubic inch (5.9-liter) displacement.

Do all nascars have the same engine?

No, not all NASCAR engines are the same; Ford, Chevrolet, and Toyota each have their own distinct V8 engines, but all engines must adhere to strict NASCAR regulations for displacement (358 cubic inches), natural aspiration, and using pushrod-actuated valvetrains. These rules ensure competition is fair, even though the engines are made by different manufacturers and have variations in design.
 
Key similarities enforced by NASCAR: 

• Engine Type: All engines are naturally aspirated V8s.
• Displacement: They must all be 358 cubic inches (approximately 5.9 liters).
• Valvetrain: The engines use traditional pushrods rather than overhead cams.
• Fuel System: All engines must use fuel injection systems.

Key differences between manufacturers:

• Manufacturer: Chevrolet, Ford, and Toyota produce their own engines. 
• Design: While conforming to NASCAR’s specifications, each manufacturer can incorporate its own design elements and features into its engine. 

Why the rules are so strict:
NASCAR’s regulations are designed to level the playing field, preventing any one manufacturer from gaining an unfair advantage. This means that while the brand names on the engines differ, the engines themselves are nearly identical in performance specifications to maintain close competition in the races.

How much horsepower do NASCAR cars have?

NASCAR Next Gen cars currently produce around 670 horsepower for most tracks, but use a restrictor plate to limit power to about 510 hp on high-speed superspeedways. However, NASCAR is seriously considering an increase to around 750 horsepower for the Cup Series, a level consistent with the previous car generation. 
Horsepower by Track Type 

• Intermediate, Road Courses, and Short Tracks: For these tracks, the Next Gen cars are tuned to produce approximately 670 horsepower.
• Superspeedways: To reduce speeds and ensure safety, NASCAR uses restrictor plates on the fuel injection ports for tracks like Daytona and Talladega, lowering the engine’s output to about 510 horsepower.

The “Horsepower Debate”

• Fan Sentiment: Many NASCAR fans and drivers support a return to higher horsepower, which was more prevalent in the years before the Next Gen car. 
• Safety Concerns: The use of restrictor plates and lower horsepower figures is a deliberate safety measure to control speeds on superspeedways, which can reach over 200 mph. 
• Cost Implications: While a return to 750 horsepower would be relatively easy with the current engine, increasing to a much higher level, like the 900+ hp of older cars, could be more expensive and shorten engine life. 
• Future Possibilities: NASCAR has also been testing a hybrid powertrain for the Next Gen car, which could potentially lead to further changes in the future. 

Current Discussions 

• In May 2025, NASCAR Senior Vice President Elton Sawyer stated that increasing horsepower in the Cup Series is “on the table and is being discussed daily”.

Do Chevy Nascars use Chevy engines?

The Chevrolet engine in Cup is called a R07. 2. That’s a 5.8L two-valve per cylinder V8. Its roots are in the small block Chevy era from 50-plus years ago.