Add plastics, and take away weight, cost, and extra components. For the latest take on this increasingly popular automotive-engineering strategy, check out this plastic front-end module (FEM).

Made almost entirely from thermoplastics-either injection molded glass-fiber-reinforced PBT or compression molded glass-mat-reinforced polypropylene-the module plugs the gap between the front fenders. Its lone metal component, a simple steel stamping, serves as the lower radiator support.

Thanks to the combination of engineering plastics and use of metal where needed for structural reasons, the module in computer simulations withstands loads similar to those seen by the metal structures it replaces. These include impact loads up to 1800 lb, which approximate hood slams and five-mph bumper impacts. Simulations also show that the module has enough stiffness to prevent "jounce" (NVH), and to tolerate the 500-800 lb loads of a full-speed "hood fly-open." Electronic tolerance analysis shows that the module can hold the 1-2 mm cross-car dimensional tolerances that OEMs require.

The design-freedom offered by molded plastics provides component integration opportunities, including latches and elements of the cooling system (both shown here). Modules with the maximum amount of integration promise to save as much as one third of the weight and cost of traditional front-end structures.

Bob Nelson, GE Plastics, 25900 Telegraph Road, Southfield, MI48034 ; Tel: (248) 351-8492; Fax: (248) 351-8465.