GM L3B engine

The GM L3B engine is a turbocharged four-cylinder gasoline engine designed by General Motors. It is an undersquare aluminum DOHC inline-four displacing 2.7 liters (166 cid) and tuned for strong low-end torque. In addition to GM's active fuel management, start-stop system, and variable valve timing, which are already featured on GM's other full-size pickup truck engines, this engine also features GM's Intake Valve Lift Control which has 3 different intake cam profiles that are electromagnetically actuated to provide improved fuel economy and performance at a wider range of operating conditions. The BorgWarner developed turbo can produce up to 27 psi (1.9 bar) of boost thanks in part to its unique dual volute turbine housing and an electrically actuated wastegate. Instead of two side-by-side exhaust passages like on a regular twin-scroll turbocharger, in this design the two exhaust passages are concentric and allow for better use of the exhaust pulse energy.