1992 Acura Legend Structure
The bodies of the second-generation Legend Sedan and Coupe, introduced for the 1991 model year, are completely different from the first-generation Legend Sedan and Coupe. To meet their goals of higher quality, both visual and functional, Legend engineers gave both bodies more rigid cabins, thicker exterior panels and improved corrosion resistance, and incorporated a host of detail refinements. To help maintain the efficiency for which the Legend is known, while improving its performance and comfort, they employed sophisticated weight-saving techniques throughout the unit-body structure.
High goals with respect to rigidity,passive safety and corrosion resistance were set for the new Legend bodies. The engineering staff strove to selectively increase rigidity, particularly in the cabin area, to improve both the perception of build quality and the overall integrity of the body. The result is an increase in overall rigidity, by 30 percent in bending and 32 percent in torsion (static values), with minimal weight increase.
To accomplish this, the latest NASTRAN computer-aided structural analysis and design programs were applied. A multitude of detail structural measures resulted. Wherever possible, for example, body pillars are interconnected by horizontal structural members in straight lines; frame areas are connected with smooth members of constant cross-section; pillars and horizontal frame elements are connected with closed-section members.
The inner and outer door panels are thicker (0.85 mm vs. 0.75) and thus more rigid. The thickness of most outer body panels, except the front fender panels, has also been increased from 0.70 or 0.75 to 0.85 mm- adding not only a further increment of rigidity but increasing resistance to minor dents. As a result, cabin rigidity has been increased 27 percent. Thanks to excellent management of impact loads, primarily due to straight front frame-members made possible by the longitudinal powertrain, there is less longitudinal cabin deformation in frontal impacts. Four honeycomb panels are bonded to the floorpan just ahead of the front and rear seats. Consisting of formed organic material between steel plates, the light, remarkably strong honeycomb material stems from jet aircraft technology.
All critical body panels are galvanized (zinc-coated). In fact most areas are zinc coated on both sides. The only body-in-white component not galvanized in the new Legend body is the roof.
FIT AND FINISH
In their quest for quality, the Acura body engineers analyzed every gap - between body panels, between hood and trunk and the body, and at points where separate units such as headlights and taillights mount to the body. Over the various areas of the body, all gaps were reduced, and some were eliminated entirely. A 4-coat/4-bake, 23-step finishing process enhances corrosion protection while contributing to the durability and quality appearance of the Legend. Corrosion resistant coats include zinc phosphate, sealant, a chip resistant lower-body primer and a PVC undercoat. Additionally,waxis injected into areas where moisture might accumulate. The air dam, front-fender leading edges, the hood's forward portion and the rocker panels are coated with a layer of flexible plastic prior to painting to help prevent chipping.