The Monte Carlo is one of several 2006 General Motor's models that launch their newest family of powertrain control systems and a new approach to powertrain development. The Monte Carlo has variable valve timing (VVT) in the new 3.5L and displacement on demand (DoD) and VVT in the new 3.9L V-6 engines. The 3.5L V-6 produces 211 horsepower (157 kW) and 214 pound/ft. of torque (290 Nm), while the 3.9L achieves an estimated 242 horsepower (180 kW) and 245 pound/ft. of torque (332 Nm).
GM's powertrain module already controlled engine and transmission functions such as fuel, throttle, ignition, emissions, and shifting. In addition, it handled other integrated vehicle functions including trailer/towing modes, traction and stability control, air conditioning, antitheft systems, and driver display information. VVT and DoD add another level of complexity. VVT controls the duration or timing of the intake and exhaust valves while the engine is in operation to improve low-end torque and reduce emissions.
DoD is a cylinder-deactivation system that delivers fuel economy improvements of 6% to 8% on the regular EPA mileage test and up to 25% under normal conditions in real world driving. In the DoD system, solenoid-controlled electronic valves direct the flow of high-pressure oil to the lifters in a sequenced manner. The position of the solenoid valve either activates the valve lifter enabling normal V-6 valve train operation or deactivates the lifter, which disables half of the valve train, allowing the engine to operate on three cylinders.
ALL IN THE FAMILY
With their family strategy for powertrain control systems, GM addresses the growing complexity of powertrain software and hardware. According to Rich Taylor, executive director, powertrain electronics and integration, “The new family approach enables greater software and component reuse to help reduce costs and improve quality. We also will be able to move to market more quickly and can focus our efforts more sharply on innovation and new technology.” By applying standard manufacturing and service procedures across the board, GM's strategy reduces the design and test workload and allows quick technology upgrades.
GM established three levels to control different types of engines. In the 2006 models, GM has addressed mid-level system features with its E38 32-bit engine controller that covers engines with improvements such as variable valve timing or displacement on demand in the Monte Carlo and Impala models. The first level with the least complex engines will not start until the 2007 model year. The top system uses an E67 32-bit engine controller for GM's most demanding engines, and has already appeared in vehicles controlling the 4.4L Northstar V-8 SC on the Cadillac STS-V and XLR-V.
A common software package and standard interfacing with the controller hardware, allows GM's computer system and software engineers to reduce their software development time. In addition, the family strategy benefits system hardware with identical packaging and mounting of controllers and their mating connectors in nearly every GM vehicle. With more than one supplier for control modules and other system hardware such as sensors and actuators, GM views commonality and collaboration in the software area as essential to maintain quality control as well as improve software build time, and lower infrastructure and support costs.