INTRODUCTION
The Acura Legend Coupe is an exclusive personal luxury car which incorporates Honda Motor Co., Ltd.’s latest technology and is built to the highest quality standards. It is the flagship of the Acura Division of American Honda Motor Co., Inc.
The Acura Division is entirely separate from the Honda Automobile Division and has its own dealer network, sales, parts, service and support system. The first Acura dealerships opened on March 27, 1986 and by year’s end there were 150 dealers nationwide; by the end of 1987, the Acura Division will be expanded to 300 dealerships. In its first nine months of operation, calendar year 1986, the Acura Division had sales of 52,869 units, including 25,062 Legends and 27,807 Integras. The projection for 1987 is 105-115,000 units.
The Legend Coupe is positioned to compete against the finest European automobiles, including Mercedes-Benz, BMW, Volvo and Saab, in every category from performance and elegance to value and reliability.
It’s a car designed and engineered for intelligent drivers who demand excellent all-around performance and handling, and expect a high degree of comfort and convenience. As a 2-door coupe, it occupies a unique place in a segment of an upscale market dominated by 4-door sedans. It also expands the Acura line, which includes the Legend 4-Door Sedan, and Integra 3-Door and 5-Door Sedans introduced last year.
The Legend Coupe offers performance, luxury and distinctive aerodynamic styling. With an innovative “thin pillar” design, sharply angled windshield and rear window, and smooth body surfaces, the Coupe registers a low 0.30 coefficient of drag in the wind tunnel.
It is powered by a 161 horsepower, 2.7 liter, SOHC, 24-valve V-6 fuel-injected engine that uses an innovative Variable Intake Control System which improves low- and mid-range response with no undesirable effect on economy or top end performance. A new dual-mode electronically controlled 4-speed automatic overdrive transmission is also available. The front-wheel drive Coupe uses equal-length halfshafts, speed-sensitive power assisted rack-and-pinion steering, and independent double wishbone suspension front and rear.
There are three versions of the Legend Coupe: standard version, L, and LS. (The LS Coupe will be introduced in late spring of 1987.) All are basically identical and are equipped with a complete range of standard features, from a power-operated sunroof to 4-wheel disc brakes.
The L and LS versions add Honda’s new, advanced Anti-Lock Braking (ALB) system, leather upholstery, computerized trip and vehicle function Information Center, Automatic Climate Control and Security System.
The ALB system incorporates two hydraulic circuits and a central computer to prevent lock-up of any wheel while braking in emergencies or on slippery roads, helping the driver to maintain stability and steering control.
The LS version also has a Honda-designed Supplemental Restraint System (SRS) with driver’s side air bag, and an audiophile BOSE@ stereo system specially designed for the Legend Coupe.
Designed primarily for the American market, the Legend Coupe’s development process began shortly after that of the Legend Sedan. While it shares some of the Sedan’s design cues, it is a completely different vehicle, with no interchangeable body panels and only a few common suspension, driveline and structural components.
The Coupe joins the Legend 4-Door Sedan and sporty Integra 3-Door and 5-Door Sedans in the Acura lineup. The Legend Sedan is a comprehensively equipped luxury touring sedan powered by a 2.5 liter, SOHC, 24-valve, fuel-injected V-6 engine; the Integras are sports sedans which combine the power of a 1.6 liter, 16-valve, DOHC engine with hatchback versatility. In its first year of competition an Integra coupe, driven by Doug Peterson, won the IMSA Champion Spark Plug Challenge Drivers’ Championship.
1987 Acura Legend Coupe Drivetrain
ENGINE
The Acura Legend Coupe is powered by a multi-point fuel-injected 2.7 Iiter, SOHC, 24-valve, 90-degree V-6 engine. The engine is a light and compact high performance powerplant that owes much of its technology to Honda experience in Formula 1 racing. Though its basic design is similar to the Legend 4-Door Sedan’s engine, it incorporates significant changes which improve low- and mid-range performance and increase horsepower without affecting efficiency.
The most obvious difference is an increase in displacement, from 2.5 to 2.7 liters (2494 cc to 2675 cc). This was accomplished by increasing the bore by 3 mm (from 84 to 87mm). The internal architecture of the die-cast aluminum alloy cylinder block was changed to maintain the same cylinder wall thickness as the 2.5 liter engine. In addition, the main bearing supports were increased in thickness for additional strength.
Its 90? cylinder bore angle and SOHC configuration allow for both substantial power output and the relatively small outer dimensions which are necessary to achieve the low hood line dictated by the Legend’s aerodynamic design.
Both the engine block and one-piece cylinder heads are precision die-cast from aluminum alloy, used for its light weight and heat dissipation qualities; the alloy pistons are molybdenum coated to minimize friction. The block has cast iron cylinder liners and is extremely rigid. The center line of the crankshaft is within the oil pan flange. The four main bearing supports use six-bolts, four vertical and two horizontal. These “cross bolted” main bearings are similar to those employed in racing engines.
The Legend’s crankshaft, as with conventional V-6 crankshafts, has three throws and four main bearings. To overcome the problem of vibration caused by the uneven firing intervals associated with a 90° V-6, the crank pins are offset by 30°. This makes the firing interval an even 120°, resulting in smooth running, especially at idle.
The cylinder head is a complex, one-piece casting, with no separate cam case. The cams are located within the center line of the intake valves and actuate self-adjusting hydraulic followers. The exhaust valves are actuated by means of a short link which connects the self-adjusting followers to rocker arms that open the valves.
The pent-roof combustion chamber, with a compression ratio of 9.0:1, uses four valves, at an included angle of 40°, to maximize valve area (intake valve diameter is 33 mm x 2, exhaust 27.5 mm x 2). The spark plug is in the center of each chamber for uniform and rapid flame-front propagation. The valvetrain design allows for the same efficient port shape and crossflow configuration that normally requires dual overhead cams.
The camshaft is coated with a special low friction alloy and lubricated by means of a forced-lubrication system incorporating oil galleries in the cylinder head which provide constant lubrication to the cam, bearings and finger-type cam followers. A large volume, integrated oil filter/cooler is also part of the lubrication system.
VARIABLE INTAKE CONTROL SYSTEM
To complement its programmed multi-paint-sequential fuel injection, the Legend Coupe uses a sophisticated Variable Intake Control System. It is a significant technological advance which combines mechanical precision with electronic control to increase torque from idle through mid-range rpm.
The system uses a three-piece precision die cast manifold which accommodates a throttle body, plenum chamber, butterfly valves, and dual-length tuned intake runners for each port. The compact unit fits within the engine’s 90-degree V-shape with no change in engine height.
At low engine speeds, air passes through the throttle body into the plenum. Then, the air goes to the combustion chambers through 630mm long, relatively small cross-section, rectangular ports. Their cross-section is chosen to create high intake air velocity and the length is tuned to achieve high volumetric efficiency by utilizing intake pulsation effects.
As engine speed reaches approximately 3200 rpm, the engine’s Electronic Control Unit (ECU) directs a solenoid actuator which partially opens six individual, butterfly valves. The valves are open fully at approximately 3800 rpm. This allows air to pass from the plenum into oval, funnel-shaped, 420mm long ports that are tuned for optimum volumetric efficiency. These have a larger cross-section than the longer ports, which continue to pass air after the shorter ports are opened. The butterfly valves open in two steps for a smooth, progressive transition. By improving the intake flow, valve opening duration could be decreased by five degrees.
Despite the increase in displacement and the use of a more complex induction system, the Legend Coupe’s engine weight increased by only slightly more than a pound.
IGNITION
The Acura Legend Coupe’s ignition system is fully electronic. Its distributor is controlled entirely by the ECU, with no mechanical or vacuum advance, making optimum ignition timing control possible.
FUEL INJECTION
Fuel delivery is by means of a multi-point-sequential, programmed fuel injection system, which uses technology derived from Honda racing experience. The injection system is composed of three subsystems: Air Intake, Electronic Control, and Fuel Delivery. The air/fuel ratio is kept at the optimum level by an eight bit microprocessor which analyzes information received from the following sensors:
| A | Throttle Angle Sensor-A precision shaft angle transducer monitors exact throttle position. The computer uses this information to determine fuel injection quantity during all operating conditions. |
| B | Crank Angle Sensors (TDC and #1 cylinder)- The #1 cylinder sensor tells the computer when to start the sequential injection; and the top dead center (TDC) sensor monitors engine speed. |
| C. | Coolant Temperature Sensor-A thermistor changes resistance as coolant temperature changes; the signal is used to tailor injection duration to different engine conditions. |
| D. | Intake Air Temperature Sensor-A thermistor measures intake air temperature and the computer adjusts injection duration to suit conditions. |
| E. | Manifold Air Pressure (MAP) Sensor-A precision vacuum/pressure transducer monitors engine load; the computer uses the information to determine the proper basic injector discharge duration. |
| F. | Atmospheric Pressure Sensor-A transducer measures barometric pressure; its information is used by the computer to adjust injector discharge duration. |
| G | Two Oxygen Sensors-Monitor oxygen content in the exhaust gas; the computer uses the signal to adjust injector duration to maintain stoichiometric air/fuel ratio for efficient NOx control by the three-way catalyst. |
Utilizing information from the various sensors, the correct volume of fuel is injected into each manifold runner sequentially at a specific time just prior to the intake stroke. Fuel is automatically cut off during deceleration and interrupted at 6600 rpm to prevent over-revving.
Electronically controlled idle valves maintain a constant idle speed, and ignition is provided by a fully transistorized, solid-state system. A three-way catalyst is used for exhaust gas after-treatment.
TRANSMISSIONS
The standard transmission for the Acura Legend Coupe is a fully synchronized 5-speed manual transmission with short shifter throws and a new dual-mode 4-speed electronically controlled automatic transmission is available. It incorporates a driver-selectable Sports mode; progressive torque converter lock-up capability in second, third and fourth gear; and torque converter lock-up under decelleration.
The automatic transmission is monitored and directed by an Electronic Control Unit (ECU) located beneath the passenger seat. It has an 8 bit microprocessor with 16K of memory which uses sensors to monitor throttle opening angle, coolant temperature, vehicle speed, engine rpm and five other functions. This information is analyzed and used to regulate torque converter lock-up and shift points in relation to Normal and Sport modes. The ECU can also perform 11 diagnostic functions for service technicians.
When the driver selects the Sport position by shifting from the D to S range, the transmission is directed to shift at higher rpms at partial throttle openings in 1st, 2nd, 3rd gears for quicker acceleration; pressing the S4 button on the shift console allows the transmission to shift to 4th gear while in the Sport mode. The Sport mode can also be used on long steep grades or while towing.
Torque converter lock-up occurs automatically to eliminate slippage for more efficient operation. Lock-up is available in second, third or fourth gears and, unlike other transmissions, it occurs in four increments, rather than one abrupt transition, to provide smooth operation. The transmission is unique in that it maintains lock-up while the car is decellerating.
Developing this transmission required the design of a new die-cast aluminum housing which incorporates an additional mount which reduces low frequency vibration.
FRONT-WHEEL DRIVE
The Legend Coupe’s refined front-wheel drive system uses equal length halfshafts to reduce torque steer caused by unequal constant-velocity joint angles. The right side shaft is divided into inboard and outboard sections. The inboard section is supported by a bearing and connects to the outboard section by a constant-velocity joint. The length of this outboard section matches the length of the left side halfshaft. This results in equal constant velocity joint angles and the virtual elimination of torque steer.
1987 Acura Legend Coupe Body
The body design of the Acura Legend Coupe satisfies specific structural, aerodynamic and style criteria. It had to have a streamlined, sporty look while maintaining low weight and high rigidity; it had to be aerodynamically efficient yet spacious inside; and it had to incorporate the distinctive Legend design theme.
To achieve these goals an entirely new unit body was designed; the Coupe shares only the structural underbody panels around the engine bay with the Sedan. Its surface sheet metal, platform and all the components from the A-pillar back are new.
The Coupe has a large glass area and a “hardtop” look that was made possible by using sashless doors-that is, doors without upper window frames-and a thin, almost invisible from the outside, B-pillar. Though it is smaller in cross-section, it has the same strength and rigidity as a conventional pillar because of an innovative design that incorporates two stiffeners that are bonded within the pillar. Box section members also surround the passenger compartment.
To maximize overall rigidity, the lower rear side sills between the door and rear wheel opening are strengthened with additional box sections. And the rear suspension housings, including the area around the wheelhouse, are reinforced with stiffeners that connect the damper base to the floorpan.
Drive components are isolated by mounting them on a sub-frame which is connected to the body at eight points. To further dampen vibration, the engine is cradled on a pair of hydraulic mounts. The automatic transmission has one extra mount to further minimize vibration.
AERODYNAMICS
The Legend Coupe’s profile is aerodynamically shaped with a low hoodline, high rear deck and flush surface glass area. Its aerodynamic specifications are:
- Cd: 0.30
- CI: 0.18
- Cd x A: 0.59 (6.36)
Frontal area: 1.97 square meters (21.20 square feet)
Air flow interruption is substantially reduced by the following:
- Flush-mounted, low profile (100mm) halogen headlights.
- Body-faired bumper and air dam.
- Concealed windshield wipers.
- Aerodynamically shaped outside mirrors.
- Flush door handles.
- Trimless, flush taillights.
- All glass areas are nearly flush with the body.
- Smooth underbody for improved air flow beneath the car.
- Aerodynamically flared fenders.
- Sharply angled backlight.
- High rear deck.
Months of testing were required to achieve the Acura Legend Coupe’s low 0.30 coefficient of drag. Once initial design drawings were completed, 1/5-scale models were built and tested in the Honda R&D wind tunnel. These versions were used to create the most efficient front and rear glass angle; hood height and slope; deck length; and overall shape. Then, full-scale mockups were built for further wind tunnel refinement.
Compared to the Legend Sedan, the Coupe has a smaller frontal area; lower profile headlights; its rear window rake is increased from 22 to 26 degrees; its body design is somewhat more rounded; and it has a front chin spoiler which curves down at the corners to direct air around the leading edge of the tires.
The Legend Coupe also uses fenders which are flared around the wheel openings. In addition to their aggressive appearance, testing showed that this configuration was aerodynamically very efficient.
The Acura Legend Coupe’s aerodynamic design contributes significantly to reducing wind noise, increasing performance, aiding stability at highway speeds, and improving fuel efficiency.
CORROSION PROTECTION AND FINISH
The Acura Legend Coupe makes extensive use of electrolytic zinc-coated steel, hot-dip galvanized steel and zinc pre-coated steel for improved corrosion resistance. Also, wax coating is applied under the hood and deck lid; around the engine compartment; within the lower sills and rear quarter panels; along the door edges; and inside the front fenders.
The finishing procedure for the Legend Coupe involves 23 steps beginning with degreasing the assembled body and ending with wax injection along inner panels and beneath the floor. The Coupe passes through five wash and rinse cycles and receives coats of zinc phosphate, sealant, chip resistant lower-body primer, and PVC undercoat.
The final primer and paint coats are each slow baked to assure a durable, hard finish with a high luster. This special painting method was developed for the Legend 4-Door Sedan. It is a 4- coat, 4-bake process which cures each successive layer of paint at a relatively low temperature for a longer period of time. Ordinarily, paint is baked at 180C? (356°F) for 20 minutes; with the new technique, it’s 140C? (284°F) for 40 minutes. This results in a smoother, flatter surface. On metallic colors, the last coat is clear for a high luster finish.
QUALITY CONTROL
Quality is a top priority consideration that began during the Legend Coupe’s initial design phase. As the car neared production, design engineers worked with manufacturing engineers to assure proper assembly. Fit and finish were audited on each part during the trial phase of production and parts were often redesigned based on experience gained on the factory floor to assure proper final assembly and fit.
Several new techniques were developed to enhance quality. For example, to assure correct window fit and operation, the doors are removed from the body after painting for window installation. They are held fast in a special jig, making it easier for workers to install the glass and window mechanisms with greater precision than if the doors were left on the car.
During production, each car goes through a car wash shower test. Also, the potential for wind leakage is regularly checked on the line by special instruments which measure the deflection of the rubber seals around the windows.
INTERIOR
With its low beltline and large glass area the Acura Legend Coupe provides an airy and open interior environment for its occupants. Its thin pillar design and low angled hood make for excellent driver visibility. The Coupe can accommodate five people. There are three-point seat belts in all the outboard seating positions and a two-point belt for the middle rear seat passenger.
The interior design was developed around the driver with the goal of increasing efficiency and minimizing stress by providing a logically designed command environment. The instruments and controls are all located within easy view and reach. All the buttons, levers and switches are designed for positive feedback so that there’s no doubt when they are actuated.
Standard comfort and convenience features include cruise control; power-assisted rack-and-pinion steering; bronze tinted glass; power operated glass sunroof with sliding sunshade; power door locks and windows; air conditioning; AM/FM cassette stereo with driver remote control; and illuminated entry system.
SEATS
The front seats in all Legend Coupe versions have fore-and-aft and seat back angle adjustments. The headrests tilt and the driver’s seat has adjustable thigh and lumbar support as well. The driver’s seat of Land LS Coupes has electric fore-and-aft and back-angle adjustment. The seats are upholstered with cold molded, ergonomically shaped, variable density urethane foam cushions with the proper degree of firmness to provide support and comfort on long trips.
Moquette upholstery is used in the standard Legend Coupe; leather seating surfaces and trim are standard equipment on Land LS versions.
SECURITY SYSTEM
The Land LS versions of the Legend Coupe are equipped with a security system designed to protect against common types of break-in and theft: forcing a door lock or ignition.
There is no special activating procedure; the system is armed 15 seconds after locking the door and a dash-mounted LED is activated to inform the driver that the system is functioning.
Opening the hood, doors or trunk without the proper key triggers the alarm; the horn sounds and the headlights flash intermittently for two minutes, and the ignition circuit is disabled. There are three horns in separate locations, making it impossible to silence the alarm by cutting a single horn wire. The system is deactivated by unlocking a door or turning the ignition key beyond the accessory position. The trunk can be opened with a key, but the system still remains activated.
INFORMATION CENTER
The L and LS versions of the Legend Coupe have a computerized Information Center which is located in clear view above the central console. It has a large fluorescent dot matrix display for information readouts.
The system performs three basic functions: providing maintenance interval information; fluid level information; and trip information. Normally, the clock function is displayed. Information displays can be called up by pushing the SYSTEM CHECK and TRIP FUNCTION switches which flank the display screen. These switches flip up to reveal buttons used to calibrate and reset the system.
The operating information presented includes:
- NEXT SERVICE DUE (shown in descending mileage from 7500, the recommended interval)
- CHANGE OIL FILTER (which may be preset in intervals up to 7500 miles) ENGINE OIL LEVEL
- COOLANT LEVEL
- WASHER FLUID LEVEL
When the interval displays reach 500 miles to go, an amber warning light goes on. When the levels are correct, the displays read OK and a green warning light is shown; when they’re below the proper level, the OK is replaced by an amber warning light and the appropriate display appears.
The trip information presented includes:
- DISTANCE TO EMPTY (shown in miles remaining) The display changes to FUEL REMAINING (in gallons) when fuel drops to 2.5 gallons and to FUEL EMPTY at less than one gallon. An amber warning light comes on at 2.5 gallons remaining.
- TRIP (which displays the time and trip miles)
- CURRENT FUEL ECONOMY
- AVERAGE FUEL ECONOMY
Oil and coolant information are based on a static check and are not available when the engine is running. A warning light indicates when oil or coolant fall below recommended levels.
If any of the monitored levels are not as they should be, the system emits a short audible signal when the ignition is switched on to bring the condition to the driver’s attention.
AUTOMATIC CLIMATE CONTROL
In addition to the air conditioning system standard on all Legend Coupes, the L and LS versions have a computerized Automatic Climate Control system. It can be preset to keep the temperature at a constant level regardless of outside temperature fluctuation.
The system uses five sensors to monitor inside air temperature, ambient air temperature, the intensity of sunlight, engine coolant temperature, and the air conditioner evaporator temperature. This information is analyzed by an Electronic Control Unit (ECU) which adjusts cold air or heater output, and the variable speed fan, to maintain the preset temperature. The system can also be operated manually; this allows the vent levels to be set as desired, the air conditioning to be turned on or off, and the fan to be run at low, medium or high speed.
The system also diagnoses itself for malfunctions. If a failure occurs, pushing the OFF and AUTO buttons simultaneously will display a code that pinpoints the location of the problem on the manual operation control panel.
The ventilation system of the Legend Coupe includes a Y-shaped duct which delivers air to rear seat passengers and exhaust vents on the rear panel which draw air out through ducts located near the rear bumper; these are low pressure areas which use the car’s motion to pull air through the cabin; their remote location and flush surface reduce wind noise.
STEREO SYSTEM
The Legend Coupe is equipped with an AM stereo/FM stereo radio with cassette deck which delivers superior sound through a 20 watt per channel 4 channel amplifier and programmable seven band graphic equalizer. It has dual-function, push-button controls; easy-to-read digital display; and four speakers.
All Legend Coupes have an FM diversity antenna system. The reception of the rear window-laminated and rear fender-mounted diversity antenas is constantly monitored and the only receiving the better FM signal is automatically selected. The Legend Coupe also has remote controls for volume, preset station selection, and cassette play selection on the instrument pod to minimize driver distraction.
BOSE SOUND SYSTEM
The Legend LS Coupe is equipped with a specially designed BOSE audio system. It’s based on psychoacoustic principles formulated by Dr. Amar G. Bose, an MIT professor well known for his revolutionary speakers and high fidelity products. Dr. Bose’s approach is to design technologically advanced, reliable audio systems for a specific environment; the goal is to achieve sound reproduction approaching the realism of a live performance.
Studies were done by BOSE engineers to determine the Legend Coupe’s acoustic characteristics; this data was supplemented by tests using life-size mannequins fitted with instrumentation that simulates human hearing. With the mannequins in the front seats it was possible to precisely locate and aim the speakers to achieve a desired frequency response over a broad volume range.
Four full range speakers are used, two in specially designed enclosures in the front corners of the doors, and two behind the rear seats. Each speaker is fitted with an individual amplifier and electronic equalizer.
The front speakers are 4.5-inches in diameter and are sealed in enclosures shaped to make the best use of the available acoustic volume within the doors. They include a tuned bass: reflex port which increases the lower frequency range. The rear speakers measure 6×9-inches and are mounted at the proper angle to reflect sound off the rear window. Ideal left/right balance is built into the system, making a separate balance control unnecessary.
The AM/FM stereo tuner with cassette deck, Dolby noise reduction, and Dynamic Noise Reduction (DNR) has been simplified for easier use. In addition to the basic controls for tuning and tape deck operation, one-knob controls operate the front/rear fader, bass and treble levels.
AUTOMATIC SEAT BELT PRESENTER
The Land LS versions of the Legend Coupe are equipped with a drivers’ side pivoting arm that swings up to place the seat belt buckle within easy reach of the driver. This occurs automatically when the driver shuts the door. When the belt is unlatched, and the door is opened, the arm retracts and lies flat against the floor easing entry to the rear seats.
1987 Acura Legend Coupe ALB/ SRS
ANTI-LOCK BRAKING (ALB) SYSTEM
The Land LS versions of the Legend Coupe are equipped with an Anti-Lock Braking (ALB) system that prevents lock-up at any wheel. It was designed by Honda Research and Development Co., Ltd. This in-house approach was chosen to permit more efficient integration of the ALB system into the Coupe’s design and to assure that the latest appropriate technology could be utilized. It has been designated ALB to distinguish it from systems made by Bosch, Teves, Lucas and others that are being used by a number of auto makers.
The ALB system is substantially different from the others in both principle and design. Honda holds numerous patents on new technology created during the ALB system’s development.
Unlike other systems, Honda’s ALB has two hydraulic circuits linked by an electronic control circuit. The primary hydraulic system functions in the conventional manner, using a master cylinder and power assist to operate the brake calipers. Under normal conditions, this system provides all the braking.
Sensors monitor velocity at each wheel, constantly relaying this information to the Electronic Control Unit (ECU). It analyzes the data, and if it determines that lock-up is imminent, the ALB system is activated. The system has its own hydraulic reservoir, pump and a modulator unit which contains three pairs of solenoids (one pair for each front wheel, and one pair for the rear wheels) and four control pistons (one for each brake caliper). The solenoids direct the pistons, cycling them up to ten times a second The two hydraulic systems intersect at each control piston.
In actual use, this is what happens: Impending lock-up is sensed at any wheel. The computer actuates the solenoid valves, which modulate the control pistons. The action of these pistons causes the pressure of the fluid in the primary line to fluctuate, or cycle, applying and releasing the brake caliper up to ten times a second. This allows the wheel to continue to rotate so the driver can maintain steering control even under maximum braking.
A key feature of the Honda ALB design lies in the independence of the two hydraulic circuits. It is a “fail safe” system. Should a failure occur in the ALB hydraulic circuit, normal braking will be provided by the primary hydraulic circuit. If the ALB system computer detects failure, an instrument panel warning light goes on.
Also, continuous pressure in the ALB circuit makes failure detection a constant function. (The ALB pump maintains this pressure by operating intermittently.) Thus, any system leak is readily apparent.
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
The driver’s side of the Acura Legend LS Coupe is fitted with an air bag and knee bolster that are designed to supplement the car’s three-point seat belt. This system was designed specifically for the Legend Coupe by Honda Research and Development Co., Ltd. and incorporates numerous patented innovations which help assure the system’s integrity and reliability.
The air bag is housed in the steering wheel hub. In the event of a frontal crash that exceeds the force of a ten mph barrier impact, the bag is inflated within 30-40 milliseconds to cushion the driver’s head and upper torso, and then quickly deflates.
The system uses four sensors to detect an impact. Two are located at the forward right and left corners of the car; two are beneath the dashboard in the passenger compartment. These sensors detect an impact within ten milliseconds and activate a propellant that inflates the air bag. Before the air bag can be deployed a signal must be received from both a front and a passenger compartment sensor. This is to prevent inadvertent deployment should one of the front sensors be struck by a localized impact; significant sudden motion at the passenger compartment must also be detected before the bag can be triggered.
To assure durability, the front sensors are epoxy potted and hermetically sealed. And, in case the electrical system fails in a crash, the CPU contains a back-up capacitor which stores electricity for 10-15 seconds, long enough to deploy the air bag. However, for service the system is disarmed simply by disconnecting the battery.
The SRS system is designed to be maintenance-free for a minimum of ten years. Special components have been developed to assure its integrity and longevity. They include coiled-wire reel on the steering column which permits steering wheel operation without the use of slip ring or sliding contacts; a double-sealed, thick-walled metal capsule to contain the solid propellant which inflates the bag; and eight multi-pin connectors in the main wiring system with gold-plated pins for better conductivity and corrosion resistance.
1987 Acura Legend Prices and EPA Mileage
| LEGEND | . | City/Hwy |
| MANUAL |
$19,898 |
20/25 |
| AUTOMATIC |
$20,523 |
19/24 |
| . | . | . |
| WITH SUNROOF | . | . |
| MANUAL |
$20,548 |
20/25 |
| AUTOMATIC |
$21,173 |
19/24 |
| . | . | . |
| INCLUDING LUXURY OPTION PACKAGE | . | . |
| MANUAL |
$22,348 |
20/25 |
| AUTOMATIC |
$22,973 |
19/24 |
| . | . | . |