'Thor' is a 4.0-Liter Four Cylinder That Can Make More Than 1,500 HP
More than 375 horsepower per liter sounds like a recipe for success.
Too long have the four cylinder tuners been poked fun at. Some of the fastest cars on the drag strip or at time attack events are powered by these high-powered, volumetrically efficient power plants, and now, we may have seen the craziest example yet. This engine, dubbed "Thor", is a 4.0L four pot that's capable of making roughly 375 hp per liter, eclipsing 1,500 hp in some applications. It's built by Elmer Racing in Finland for top motorsport applications and will soon be on sale for the price of €120,000 ($140,490).
The engine, built specifically for hillclimb and time attack applications, is a rev-punching sweetheart that makes power all over the place. Lightweight billet materials are used to construct 'Thor' and turn it into a resilient piece of kit that can stand the constant abuse of motorsports while keeping competitiveness as the top priority. Beautiful components make up this power-crazed engine, promising that it will be strong enough to withstand the crazy internal force.
When asked by The Drive what advantages this high displacement four cylinder yields over a similarly powerful V8 unit, Elmer Racing explained, "A V8 engine designed for racing can have a very high torsional rigidity. And lots of race classes have minimum weight limits, which create a necessity for very high powered (expensive) engines, with less importance on weight. Racing v8 engines suit these kinds of classes well.
"However, for unlimited class racing the weight penalty of a v8 is unacceptable."
As a result, the team opted for "Thor". Compact packaging and extreme weight reduction makes it a more viable option for these cars that run in pro and unlimited classes, allowing them to hit their targets for performance without sacrificing agility or cornering.
It will first be used in Rod Pobestek’s Porsche 968 RP968 for next year's World Time Attack Challenge. The team is expected to run it at a conservative 8,500 RPM, though Elmer Racing has projected that it will run without issue at as high as 10,000 RPM. Although not unusual for race-inspired four cylinders, that's a considerable redline for an engine with a displacement of four liters.
Here you can see bits and pieces of the engine's build process as it explains in detail what goes into such a wicked powertrain.