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General Motors adds a larger displacement more powerful variant to its global 4-cylinder engine family. The new Ecotec 2.4L VVT, being introduced in the 2006 Pontiac Solstice is the latest variant within the Ecotec engine family. This new engine is built on the heritage and excellent reputation of the Ecotec 2.2L(1), the global 4-cylinder engine introduced for the North American market in the 2000 model year Saturn L-series. Ecotec engines are now offered in many additional GM platforms in North America as well as in Europe. The Ecotec 2.4L VVT shares many parts with the Ecotec 2.2L(1), with addition of cam phaser technology to enable variable valve timing (VVT) along with several structural enhancements. The Ecotec 2.4L VVT produces 25% more power, impressive torque at lower engine speeds and offers a number of other advantages.

To satisfy the performance demands of the mid-Size passenger car market, General Motors has introduced a new 60° V6 engine called the Twin Dual Cam V6. This engine, with a displacement of 3.4 liters, has many modern technology features such as: four valves per cylinder; direct acting overhead camshafts; compact, pent-roof combustion chamber with a centrally located spark plug; multi-point electronic fuel injection with dual spray injectors; and several noise attenuation features. This paper describes the technical features of the engine and the manufacturing techniques implemented so as to assure high quality. Also included is a description of the operating philosophies practiced throughout the project with the use of Quality Function Deployment, Product Development Teams and Simultaneous Engineering process.

Engine mounting system tuning by experimental methods used during vehicle development is a very time consuming process. The degree of system optimization achieved relying on this approach alone is highly dependent upon the development engineer's experience, the allowable flexibility in modifying the system late in the vehicle program and the available time before the vehicle is scheduled for production. This situation should be helped if the initial mounting configuration provided to the development activity is near optimum. Defining a near optimum initial mounting configuration is not an easy task by any means due to the complex nature of the powerplant inertia properties, the packaging constraints on the mount locations, as well as the individual mount rate ratio limitations imposed by manufacturability.

Two types of computer simulations are used extensively by Chevrolet to analyze vehicle suspension systems. The first is a nonlinear static analysis and the second is a linear dynamic analysis. These simulations are used to help evaluate proposed suspension designs for loads, dynamic force transmissibility, and various ride and handling characteristics well before prototype hardware is built and tested. Load outputs from these simulations are input to finite element models to analyse stresses in frames, control arms, and other related vehicle components of interest.