The Gen V family of small-block engines welcomed three more members today as GM introduced a line of EcoTec3 engines for the 2014 Silverado/Sierra full-size pickups.
Truck customers will soon be able to choose between 6.2-liter and 5.3-liter V8 engines as well as a 4.3-liter V6 version. Horsepower and torque numbers were not released, but GM officials promised the engines are “specifically designed for the way customers use trucks in the real world.”
“They have all the power and torque needed to confidently handle the tough jobs,” adds Jordan Lee, chief engineer for the small-block program.
All three engines feature similar technologies found on the 6.2-liter Corvette engine that was introduced in October: direct injection, cylinder deactivation and continuously variable valve timing. While the Corvette engine is designed for performance to enhance the driving experience of a sports car, the truck engines will be tuned for towing and durability.All three have aluminum blocks and boast an 11:1 compression ratio, except the 6.2 that has 11.5:1. All three have a 92mm stroke (3.62 inches) crankshaft with cylinder bores of 3.92 inches for the V6 and 3.78 and 4.06 inches for the 5.3L and 6.2L, respectively. The cylinder head design appears identical to the Corvette engine, based on excerpts from the press release: switched intake and exhaust valve positions, revised spark-plug location, pistons with unique topography, large rectangular intake ports with a twist to enhance mixture motion and the “advanced combustion system.”
The intake manifold wasn’t mentioned in the press release, but the from the photos it appears to have long, curved runners for added torque, as opposed to the shorter, straight runners on the Corvette engine.
One difference will be in Active Fuel Management (AFM) or cylinder deactivation system. The two V8 engines will cut half the cylinders in AFM mode while the V6 cuts just two to run as a V4 in light-load conditions.
Other features follow the Corvette engine architecture: variable-displacement oil pump with dual-pressure control, oil-jet piston cooling and offset water pump. The V6 engine will have a 6-quart oil capacity while the V8s have an 8-quart pan, and 0W-20 will be recommended for the V8 engines. All engines will also utilize the E92 engine controller and 58x ignition system.
More information to follow as GM releases power numbers and other details.