Back in 2019, General Motors introduced a new four-cylinder engine in the Chevrolet Silverado pickup truck. Developed specifically for the midsize truck, the engine eventually made it into the Cadillac CT4-V sedan for the 2021 model year. So what's so special about this engine? Well, for starters, it's pretty big for a four-cylinder at 2.7 liters. It also features a dual volute turbocharged design instead of the more common dual scroll layout. And the folks at Engineering Explained talk about this feature and what kind of benefits it brings to the table.

The dual volute design improves response and low end torque

The dual volute design is actually similar to the dual scroll layout. This means that exhaust gas enters from opposite sides of the turbine. With the dual scroll design, gas from the two chambers enter together, and this causes an overlap that decreases efficiency.

There's no specific word on that efficiency compared to other turbo designs, but GM says that at 1,500 rpm, you can get to 90-percent peak torque in 1.9 seconds. That's impressive for a turbocharged engine in general but still slow compared to an electric drivetrain, for example.

The three-position camshaft improves fuel economy

Another interesting feature is the three-position camshaft, which basically shifts the engine from running in a performance-oriented mode into a more economical mode with just two cylinders. The latter obviously helps save fuel. However, Engineering Explained argues that while this feature improves fuel economy in the city, it's not as efficient on the highway. At least not in the Chevrolet Silverado, which returns 23 mpg with the four-cylinder and 24 mpg with 5.3-liter V-8. The Cadillac CT4-V is obviously more economical at 29 mpg on the highway.

Both versions of the engine generate more than 300 horsepower

As of June 2020, the 2.7-liter four-cylinder powers two vehicles from General Motors, and both come with more than 300 horsepower on tap. The Chevrolet Silverado benefits from 310 horsepower and 350 pound-feet of twist, while the Cadillac CT4-V cranks out 325 horses and 380 pound-feet of torque. The mill will probably make it into other GM vehicles in the future.