Dual-volute SALUTE!

BorgWarner's new twist in turbocharging helps GM's new L3B gasoline four deliver V6-beating power and torque, with diesel-like fuel efficiency, in full-size pickup trucks.

GM's all-new 2.7-L L3B was designed for truck use, with a wealth of advanced features (see https://www.sae.org/news/2018/05/gm-2.7-l-i-4-revealed). The result is 9% more power and 14% more torque than GM's incumbent LV3 4.3-L V6. Teamed with the 8L90 8-speed Hydra-Matic transmission, the L3B turbo four is the base engine for 2019 Chevy Silverados in LT and RST trim and also is offered in the 2019 GMC Sierra.

Engineering a boosted I4 for full-size pickups' broad duty cycle was no mean feat. Such engines provide impressive economy during steady-state cruising in top gear and generate ample thrust under load once the revs and boost are up. The challenge is in the transition between those operating modes-when the engine must leap into action as the throttle is quickly moved from barely open to WOT.