4.0L Four-Cylinder Racing Engine Makes 2,000+ HP

For a street car, you might consider 400 horsepower to be a mighty figure for a highly-tuned four-cylinder engine. For the boffins at Elmer Racing, though, that’s nothing. Their latest four-banger is capable of plunging deep into the four-figure horsepower range.

As reported by Engine Swap Depot, the four-cylinder engine known as Thor has a power output befitting its name. The latest version of the turbocharged 4.0-liter engine is capable of delivering 2,000 hp in racing trim. If drag racing is your game, it can be configured for between 4.0 to 4.4 liters of displacement, with power figures rising as high as 3,000 hp.

The engine is specifically built with an eye to minimizing weight while maximizing power output. In weight-limited racing classes, V8 engines can do great. However, for certain “unlimited” class cars in disciplines like Time Attack, the weight penalty of a V8 can be a disadvantage. A smaller, lighter four-cylinder can be a boon in this area. The Thor long block weighs just 233 pounds by virtue of its all-billet construction.

The first version of Thor bore out this principle well, as we explored in 2017. The original spec of the motor was capable of a still-impressive 1,500 hp, which pencils out to 375 hp per liter. Thanks to its light weight and compact packaging, it was selected as the powerplant for Rod Pobestek’s Porsche 968 RP968 Time Attack car.

With Thor putting down the power, the RP968 won the 2018 World Time Attack Challenge and later became the second-fastest car of all time to lap Sydney Motorsport Park. The engine has gone on to win three World Time Attack Challenge trophies in total, following up with back-to-back-to-back wins in 2019 and 2022.

Elmer Racing claims the engine has the best power/mass ratio of any OEM circuit racing engine ever—and that’s including F1 engines. Thor doesn’t come cheap. A long block will set you back €82,000, and that doesn’t include manifolds, sensors, wiring, or a turbo.

Elmer Racing won’t sell this engine to just anyone. The package will only be made available to “qualified teams” capable of choosing the right supporting components. For your money, though, Elmer Racing will deliver you an engine built to your exact specifications. There’s no need to fuss around with transmission adapters or the like—you can have your engine machined to fit your gearbox housing directly.