OVERVIEW
The 1991 Legend body is all-new. Though only 3.4 inches longer than that of its predecessor, it rides on a wheelbase 5.9 in. longer, thus expressing the Legend's new mechanical format (longitudinal front engine/ front-wheel drive) in altered proportions. Yetthe Acura Legend identity is clearly preserved, particularly in the rear view. To meet their goals of higher quality, both visual and functional, Legend engineers gave the new body a more rigid cabin, 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 body.
DESIGN
The new Legend shape is rounded, flowing and sporty while retaining a classic "three-box" shape. A forward-thrusting separate grille (which is part of the hood) incorporates the new Acura emblem and is flanked by integrated, near-flush headlight units with separate low and high beams in elliptical internal frames. Greater width (by 2.4 in.) is apparent here, as is the stance imp~ by wider tracks front and rear.
Inside view, the wheels-forward, short-overhang look engendered by the new longitudinal powertrain is clearly discernible, as are tighter (smaller-radius) wheel arches and a body-side character line "interrupted" by the prominent front arch. The new proportioning is accented by what the designers call a "tight" cabin, integrated with rather than separated from the lower body to give the body a sporty, organic look.
Windshield and rear-window angles, optimized for aerodynamic efficiency, are rakish; this is particularly evident in the graceful, larger rear window. At the rear, the taillight shape and spoiler-like upper body portion echo themes first seen in the sporty Legend Coupe.
FUNCfION AND FORM
In addition to its new shape, the Legend body incorporates numerous refinements that improve its functional quality. The headlights, for instance, are of a new duallens type that is aimed by internal adjustment rather than by moving the entire unit; this allows them to be mounted to the body with smaller gaps, improving appearance as well as aerodynamics. For lighter weight, the lenses are plastic.
The door mechanisms have been refined for a smoother door-opening feel and a higher-quality closing sound; the two-position door checks also operate very smoothly and are well protected from grease and dirt.
When a door is opened, a clean, well finished appearance greets the eye. To achieve this, each component was reviewed and, if appropriate, redesigned: hinges, strikers, interior-light switch (now recessed into the lock itself),seal lines, screws (now hidden). The driver's or passenger's appearance was a priority too: the doorsill garnish has been extended downward, and at the bottom of each door is a seal extending down over the body sill to keep it free of road grime that could soil clothing upon entry or exit. These seals also reduce road noise reaching the interior- an advantage especially noticeable when driving in the rain. Inside the doors are side-guard beams in a new form: variable-diameter tubes that are not only lighter, but highly efficient at transferring impact loads to the body structure. Together with other new efficiencies in the door structure, these beams helped the engineering team achieve a weight reduction of more than 23 pounds for the four doors.
Even the trunklid got its share of attention; more rigid than before, it opens and closes with a greater feeling of quality.A new lightweight sunroof frame saves nearly 31bs. while increasing head room.
STRUCTURE
High goals with respect to rigidity, passive safety and corrosion resistance were set for the new Legend body.
Higher overall rigidity was not a primary goal; the engineering staff believed the first-generation Legend body was excellent in this respect. What they aimed at was selectively increasing rigidity, particularly in the cabin area, to improve both the occupants' perception of quality and the overall integrity of the body. The result is an increasein overall rigidity,by 30 percent in bending and 32 percent in torsion (static values), with the tangible benefits at a maximum while the weight increase is at a minimum.
To accomplish this, the latest computer-aided structural analysis and design techniques were applied. A multitude of detail structural measures resulted. To the greatest extent possible, for example, 1:xxiypillars 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 (0.85mm vs 0.75)and thus more rigid. The thickness of most outer body panels, except the front fender panels, has also been increased from 0.70or 0.75to 0.85mm - 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 better management of impact loads, primarily due to straighter front frame members made possible by the longitudinal powertrain, there is less longitudinal cabin deformation in frontal impacts. An interesting detail which improves the structure's resistance to vibration and noise transmission is that four honeycomb panels are bonded to the floorpan just ahead of the front and rear seats. Consisting of formed paper between steel plates, the light, remarkably strong honeycomb material stems from aircraft practice and is also found in the Boeing 767.The C-pillars are filled with foam rubber for a further reduction in the transfer of body noise.
CORROSION RESISTANCE
An important, longterm measure of quality is resistance to corrosion. Here the proportion of body parts that are galvanized (zinc-coated) has been increased to 87 percent; in fact, the only body-in-white component not galvanized in the new Legend body is the roof, and most areas are zinc-coated on both sides. An easily overlooked, yet very real place for corrosion to start - the fuel-filler cavity - is now made of rubber instead of steel, so it ceases to be a source. This detail presents a cleaner appearance when the fuel door is opened.
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 they were able to reduce gaps by 10 to 100 percent (meaning some gaps were eliminated entirely).
A four-coat/ four-bake, 23-step finishing process enhances this corrosion protection while contributing to the Legend's durability and quality appearance. To ensure proper bonding of succeeding paint coats, there are five wash and rinse cycles. Corrosion-resistant coats include zinc phosphate, sealant, a chip-resistant lower-body primer and a PVC undercoat. Additionally, wax is 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.
Yet another detail adding to the Legend's refined appearance is the new press-integrated beltline mouldings. This manufacturing technique allows a varying cross-section along their length to impart a subtle taper. Even these mouldings' ends are finished carefully to look attractive when a door is opened.