Overview
The GM L3B engine made its debut in the 2019 Chevrolet Silverado 1500 and 2019 GMC Sierra 1500 producing an SAE-certified 310 horsepower and 348 pound-feet of torque.
The motor was developed specifically for truck applications, and the motor delivers peak torque from 1,500 to 4,000 rpm. Additionally, it makes 22 percent more torque than the 4.3L V-6 LV3 it replaces.

To help generate the strong low-end torque customers expect in a truck, it was designed with a long piston stroke of 4.01 inches (102mm), which is the distance the piston travels up and down within the cylinder.
The long stroke enables improved combustion and thus a higher compression ratio. Typically, a long stroke can increase the load of the pistons against the cylinder walls, generating more friction. That's alleviated in the 2.7L Turbo with an offset crankshaft. It is slightly off-center of the cylinders, allowing a more upright position for the connecting rods during their movement.

To support the high cylinder pressures that come with turbocharging, the crankshaft and connecting rods are made of forged steel and the pistons are made of a tough aluminum alloy with a cast iron ring groove insert.
All elements of the 2.7L Turbo were designed for the demands of turbocharged performance in a truck environment, and the engine was subjected to the same rigorous durability standards as the Silverado's proven V-8 engines
The 2.7L Turbo features an aluminum block and cylinder head for reduced mass
- GM's first use of Active Fuel Management (cylinder deactivation) on a four cylinder engine.
- High and low lift valve profiles.
- Continuously variable valve timing.
- High valve lift for full power.
- Low valve lift for balance of power and efficiency.
- Active Fuel Management shuts down two of the cylinders in light load conditions to further conserve fuel.


The 2.7L Turbo engine employs an advanced dual-volute turbocharger that elevates the performance and efficiency advantages of a conventional turbo, with quicker response and enhanced low-rpm torque production.
Rather than a single spiral chamber (volute) feeding exhaust gas from the exhaust manifold to drive the turbine on the turbocharger, the dual volute design has a pair of separate chambers with two exhaust gas inlets and two nozzles to drive the turbine. The design allows the exhaust pulses of the engine to be leveraged for faster spool-up and subsequent boost production, particularly at low rpm, where the effect significantly enhances torque output and drivability.
It works in unison with the engine's integrated exhaust manifold/turbocharger housing, which splits the exhaust channels from the cylinder head so the exhaust flows through two separate channels in the turbo housing, based on the engine's exhaust pulses. When complemented by the precision of the engine's valvetrain, that separation leverages exhaust scavenging techniques to optimize gas flow, which decreases exhaust gas temperatures, improves turbine efficiency and reduces turbo lag.

An electronically controlled wastegate and charge-air cooling system support the turbocharger and enhance its effectiveness. Compared to a conventional wastegate, the electronically controlled version offers more precise management of the engine's boost pressure for smoother, more consistent performance.
