2001 Acura 3.5 RL Press Kit

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2001 Acura 3.5 RL Press Kit

INTRODUCTION
The Acura 3.5 RL is the flagship sedan of the Acura lineup. The product of an intensive research and development effort in which every nuance of the interface between driver and car was examined, the 3.5 RL luxury sedan takes Acura to a new level of comfort, performance, refinement and human engineering. At the same time, the 3.5 RL delivers an engaging driving experience with the confident handling, immediate response, advanced safety engineering and high levels of performance Acura drivers have come to expect.

Dramatic improvements in comfort, ergonomics, noise, vibration and harshness and performance have made it the quietest, smoothest, most refined Acura ever built. The 3.5 RL is a world-class luxury sedan, competing with the likes of the Mercedes E Class, BMW 5 Series, Audi A6, Lexus GS 300/400 and LS 400, and the Infiniti Q45.

The 3.5 RL is powered by the largest engine with the most torque ever produced in an Acura sedan. The 3.5-liter V-6 engine develops its peak torque at an extraordinarily low 2800 rpm, giving immediate throttle response, authoritative acceleration and the on-demand power typical of a big-bore V-8, but with the light weight and packaging efficiency of a V-6.

The 3.5 RL comes in one fully equipped trim level, with a long list of standard luxury amenities including the HomeLink remote control system, heated front seats and door mirrors, leather trimmed interior, power moonroof, Acura/Bose" Music System with six-disc CD changer and automatic day/night rearview mirror. The RL also features Acura's highly sophisticated Vehicle Stability Assist (VSA) system as standard equipment.

In 2001, the 3.5 RL receives carpeted floor mats standard and an emergency trunk opener. The only factory option for the RL is the DVD-based satellite-linked Acura Navigation System with coverage of the continental U.S. and more than 37 million points of interest.

GENERAL CONCEPTS AND GOALS
The Acura 3.5 RL is designed to provide:

  • An unprecedented level of comfort along with top-rank driver and passenger amenities
  • The smoothest, most compliant ride of any Acura ever built, balanced with predictable, sure-footed handling and the security of a Vehicle Stability Assist (VSA) system
  • The concept of "human linearity" taken to new heights; the subjective feelings and intuitive responses of drivers and passengers have been given top priority in all major engineering decisions
  • A torquey, highly responsive V-6 engine that gives the immediate acceleration, low-rpm power and overall performance typical of a V-8, but with the lightweight packaging efficiency and fuel economy of an advanced V-6
  • A subtle, roomy, "open-feeling" interior design along with a state-of-the-art Acura/Bose music system and other top-rank amenities
  • Air conditioning and automatic climate-control
  • The strongest, most rigid sedan unit-body structure in Acura history, using a high percentage of two-sided galvanized steel for excellent durability and corrosion protection
  • A high level of sophisticated safety engineering, including dual front air bags with a dual stage passenger's air bag, driver and front passenger's side air bags with occupant height and position sensors in the front passenger's seat, front seat belt pretensioners, front-door hip and shoulder pads and advances in interior padding, and Xenon High Intensity Discharge (HID) headlights
  • Bold exterior styling, using a prominent grille and high, wide "shoulder lines" for a distinctive Acura look and feel, coupled with excellent aerodynamic performance with an emphasis on low levels of lift, predictable handling in gusty conditions and low wind noise at high speed

OVERVIEW
The Acura 3.5 RL is available exclusively as a four-door sedan in a single trim level featuring a full complement of standard luxury features and amenities.

Every 3.5 RL is equipped with an all-aluminum, 3.5-liter, single-overhead camshaft V-6 engine with four valves per cylinder, producing 210 horsepower @ 5200 rpm and 224 lb-ft of torque @ 2800 rpm. Direct ignition, Programmed Fuel Injection (PGM-FI) and a three-stage Variable Induction System enhance drivability, low-end response and overall performance. A balancer shaft is used to eliminate primary couple vibration, resulting in extremely smooth engine operation at any rpm. The 3.5 RL meets stringent LEV (Low Emission Vehicle) standards.

A four-speed, electronically controlled automatic transmission is standard. "Grade Logic Control" software is used for improved acceleration and reduced gear "hunting" while driving uphill and to enhance engine braking on downhills. A gated shifter is used to give the driver a more intuitive sense of shifter position.

The 3.5 RL features a front-wheel-drive powertrain design for lighter weight, enhanced packaging efficiency and handling stability. Four-wheel independent double-wishbone suspension ensures optimum balance of precise handling and luxury ride quality. Special low-friction joints and dampers provide improved ride compliance while hydraulic bushings are used in the rear suspension for reduced road noise. Four-wheel disc brakes with ventilated front rotors provide excellent stopping, and an Acura-designed four-wheel ABS is provided as standard equipment. The RL also features a sophisticated Vehicle Stability Assist (VSA) system that's specifically tuned to enhance the cornering and acceleration performance of the powerful front-wheel drive vehicle.

The unit-body chassis of the 3.5 RL is engineered for excellent bending and torsional rigidity for improved handling precision, a more solid feel and optimal isolation of undesirable noise and vibration.

An available satellite-linked Acura Navigation System employs GPS and gyroscope locating systems to provide audio and visual guidance. The DVD system has 14-times greater data capacity to speed route calculation time, while the big new seven-inch liquid crystal display (LCD) unit is mounted in the upper section of the center console for easy viewing.

The 3.5 RL comes equipped with an unusually long list of standard luxury features, including an interior trimmed with soft leather and burled Tendo-camphor wood; an acoustically tuned eight-speaker Acura/Bose Music system with AM/FM stereo, cassette and six-disc trunk mounted CD changer; a HomeLink remote control system; automatic climate control system; heated front seats; slide and tilt moon roof; rear-seat pass-through with ski boot; power tilt and telescope leather-wrapped steering wheel; power seats, windows and door locks; a two-program memory system for driver's seat, steering wheel and mirror positioning; auto on/off HID headlights; 16-inch cast-alloy wheels; remote keyless entry and security system; and an anti-theft electronic vehicle immobilizer system.

2001 Acura 3.5 RL - Powertrain

OVERVIEW
The 3.5 RL is powered by a 3.5-liter, all-aluminum, single-overhead camshaft, 90-degree V-6 engine that produces 210 horsepower at 5200 rpm and 224 lb-ft of torque at a very low 2800 rpm that is designed to go 105,000 miles before its first scheduled tune-up. Four valves per cylinder and a three-stage variable induction system help to provide both high torque at lower engine speeds and excellent breathing at higher engine speeds. The 3.5 RL meets LEV (Low Emission Vehicle) standards.

The 3.5 RL engine was developed with two major goals in mind: first, to provide maximum power at the engine speeds used in most day-to-day driving (1500 rpm to 4000 rpm). And second, to be both quieter and smoother than any engine in Acura history.

The engine is located longitudinally, moving weight to the rear of the car for the 60/40 weight distribution deemed optimum for a front-wheel-drive sedan. The longitudinal mounting also yields benefits in noise, vibration and harshness (NVH) performance, because it allows the use of softer and better located engine and transmission mounts.

An electronically controlled four-speed automatic transmission, with Grade Logic Control software, is standard on every 3.5 RL.

ENGINE BLOCK
Like other Acura engines, the block of the RL engine is an aluminum pressure casting with cast-in iron liners, a design known for its light weight, excellent rigidity and outstanding long-term durability. The crankcase is designed with a deep skirt and extensive webbing for added rigidity, reduced noise and reduced vibration. The RL engine is a slightly undersquare design, with a bore of 90.0 mm and a stroke of 91.0 mm, for a displacement of 3474 cc.

The main bearing journal supports are generous for added rigidity, resulting in significantly reduced vibration in the 300-to-800 Hz range. The improvement in stiffness has raised the resonant frequency of the engine block an impressive 20 Hz.

PRIMARY COUPLE BALANCER
To further reduce vibration transmitted to the passenger cabin, the RL engine features a rotating balancer shaft, mounted to the right side of the engine block. The belt-driven balancer counteracts the rocking tendency inherent in 90-degree V-6 designs.

CRANKSHAFT
The forged steel crankshaft is microfinished, an extremely precise finishing process developed originally from the Formula One engine program to reduce friction and enhance durability. The metallurgy of the main bearings is also a direct result of Honda's F1 program of the late eighties and early nineties. The surface of the bearings has a unique, pyramidal structure, allowing space for enhanced oil retention and resulting in lower friction and improved long-term durability.

BLOCK-FORGED CONNECTING RODS
The connecting rods of the 3.5 RL are forged using a unique process that results in parts of high strength and unprecedented uniformity. The RL engine is the first automobile engine in the world to be produced using this advanced technology.

Because of the imprecise nature of the conventional forging process, the connecting rods of all other auto engines must be sorted according to weight, with rods of approximately equal mass assigned to each particular engine to achieve proper reciprocating balance. Even in rods that happen to have equal overall mass, the distribution of metal density throughout conventional rods can vary enough to affect strength and engine balance.

The rods of the RL are forged with a new "block forging" system in which the steel blank is struck, at extremely high pressure, from five directions at once. This process has no allowance for excess metal; it has nowhere to go in the ultra-precise block-forging dies. Accordingly, the blanks that will be forged into RL rods are machined before the forging process, to exacting mass tolerances. In other words, the material that will become an RL connecting rod has been precisely measured and balanced before it ever enters the forging dies.

As a result of this process, RL connecting rods are the most precisely balanced of those in any production-automobile engine.

FULL-FLOATING PISTON PINS
To reduce the engine noise caused by contact between the pistons and piston pins, the RL engine uses a full-floating piston pin design in which the clearance between the piston and piston pin has been reduced. Typically the piston pin is a press fit in the rod, and a larger clearance between the pin and the aluminum piston allows the piston to rock freely. In the RL design, the pin moves freely in the rod, and the piston rocks freely on the pin as well; the piston pin is essentially free to "float" between the piston and the rod. This change alone has resulted in a significant 5db noise reduction.

CYLINDER HEAD/VALVETRAIN
The RL engine features a four valve per cylinder valve train with pent-roof combustion chambers. A single camshaft for each cast-aluminum cylinder head is driven by a flexible, toothed belt. Hydraulic lash adjusters are used for quieter running and reduced maintenance.

The combustion chamber is designed with a generous "squish" area formed by the piston and cylinder head to promote rapid and complete combustion by increasing the turbulence of the fuel air mixture around the centrally located platinum tipped spark plug.

VALVE TIMING
Conventional high-performance engines typically use a substantial amount of valve overlap to achieve better breathing at higher rpm with the intake and exhaust valves opening simultaneously at Top Dead Center between the exhaust and intake strokes. At low rpm, however, this allows blowback of the fuel-air mixture, with exhaust gas creating a pressure wave that reverses the flow of the fresh incoming charge. To prevent the resulting unstable combustion -- and relatively rough running -- at low rpm, the RL camshaft timing has considerably reduced valve overlap, resulting in smoother low-speed running and improved low-rpm torque. The advanced four valve per cylinder design, along with the Variable Induction System intake tract, combine to maintain excellent high-rpm power output.

TIMING BELT
To further reduce noise, the resonant frequency of the timing belt has been tuned by altering both its width and its material. The position of the belt tensioner was also optimized as part of the intensive effort to reduce overall engine noise.

VARIABLE INDUCTION SYSTEM
To tune the intake system volume and length for optimum torque at any rpm, the RL uses a three-stage intake system. To enhance cylinder charging by making use of resonance effects in the intake tract, the engine uses a longer intake tract at low rpm, transitions to a mid-length tract in the mid-range and then is opened completely for high-rpm running, letting the inertia effect of the moving column of air in the system enhance cylinder filling at higher engine speeds. The system has been designed and tuned for the special low-rpm/high-torque tuning emphasis of the RL engine.

PROGRAMMED FUEL INJECTION
Programmed Fuel Injection (PGM-FI) compensates for varying driving and atmospheric conditions, providing enhanced drivability and engine efficiency in a wide variety of conditions. Data on coolant temperature, air temperature and density, manifold vacuum, engine rpm, throttle position, crankshaft position and exhaust oxygen content is interpreted by the Electronic Control Module (ECM), which determines fuel injector duration and timing, as well as ignition timing and transmission operation. To reduce the pulsing noise emanating from the fuel injectors, a special sound-dampening unit is mounted at the junction of the fuel delivery tube and each individual injector.

FOUR-SPEED GRADE LOGIC CONTROL AUTOMATIC TRANSMISSION
The advanced, computer-controlled automatic transmission of the RL is the product of an intensive development program that focused on smooth shifting, responsive operation and state-of-the-art efficiency and drivability.

The transmission also uses Grade Logic Control to enhance performance on uphills and downhills. Using "fuzzy logic" software, the Electronic Control Module senses when the 3.5 RL is traveling uphill and holds the transmission in a lower gear, even if a reduction in throttle position would otherwise dictate an upshift. This prevents "hunting" of the transmission between gears in steady uphill driving. Also, on downgrades, the transmission holds third gear instead of automatically shifting to fourth, letting engine braking help keep the RL from picking up unwanted velocity.

A refined torque converter is used to enhance performance and to achieve optimum fuel efficiency. The converter has been developed to reduce the "creeping" effect at idle, making the vehicle extraordinarily easy to hold with the foot brake at a stoplight.

A gated shifter is used in the RL, helping the driver sense the position of the lever without diverting attention from the road.

ELECTRONIC/HYDRAULIC ENGINE MOUNTS
To reduce vibration at idle, the RL uses hydraulic engine mounts with two different damping rates: a soft rate that allows the engine/transmission unit to move more freely at idle and a stiffer rate that positions the powertrain more firmly during driving. Between 820 and 850 rpm, the damping characteristics of the mounts change automatically; a small solenoid valve closes, restricting the flow of fluid from chamber to chamber thus increasing the damping rate.

In addition, the main engine mounts have been located very close to the center of mass of the engine/transmission unit, more effectively isolating the primary inertial couple effect at idle. This change has resulted in significantly reduced vibration felt at the front seat in the critical 500 to 1200 rpm idle and off-idle range.

LIQUID-FILLED SUBFRAME MOUNT
To reduce engine noise under acceleration, the subframe mounts between the engine/transmission/suspension assembly are filled with hydraulic fluid of a specifically tuned viscosity. The resulting softer damping rate further isolates the passenger compartment from engine and road noise.

2001 Acura 3.5 RL - Chassis

OVERVIEW
The 3.5 RL is equipped with four-wheel independent double-wishbone suspension with coil springs, four-wheel disc brakes with ventilated front rotors, an Acura-designed Antilock Braking System (ABS) and stabilizer bars in both front and rear. The goals in developing the RL chassis were to increase overall cornering ability and make the response of the chassis to driver input as linear and predictable as possible while at the same time achieving a smooth, well-controlled ride -- and reducing noise, vibration and harshness to a remarkable degree.

Like all Acura models, the RL is designed as a true driver's car, with suspension tuning to give the car nimble and sporty handling while maintaining excellent ride comfort.

LOW-FRICTION DOUBLE-WISHBONE SUSPENSION
The double-wishbone suspension layout of the RL allows precise control of wheel movement while isolating the damper units from the side-loading and resulting friction. The front suspension uses unequal-length upper and lower control arms and a tubular stabilizer bar, while the rear suspension is a combination of a longitudinal trailing arm, three lateral links and a tubular stabilizer. For excellent stability and improved ride quality, added anti-squat and anti-dive geometries were built into the RL suspension. To achieve a compliant ride without compromising handling response or cornering capability, the RL suspension also uses a number of innovations to reduce friction throughout suspension travel. The stabilizer bars use highly efficient ball joints at either end, as well as self-lubricating bushings at the sub-frame mounts. The upper arms of both the front and rear suspension have low-friction ball-joint bushings where they attach to the main structure, reducing overall friction while enhancing rigidity of the suspension assembly. The dampers of the RL have an advanced Progressive Valve design for increased damping control at low damper speeds while retaining quick, fluid response to large impacts. Special Teflon seals within all four damper units reduce friction even further for improved ride quality.

LOW ROLL CENTER
To give the RL a stable, predictable feel during hard cornering, while improving overall lateral-acceleration capability, the suspension geometry was designed with lower roll centers than previous Acura luxury sedans. The roll center of the front suspension is 59 mm above ground level and 70 mm above ground level at the rear. This has resulted in increased cornering performance, from 0.77 g to 0.80 g, as well as more predictable response at the limits of adhesion.

LIQUID-FILLED REAR TRAILING ARM BUSHING
To reduce road noise and harshness, the bushing at the front of the rear-trailing arms is a liquid-filled design, instead of the more conventional rubber-damped bushing.

VEHICLE STABILITY ASSIST (VSA) SYSTEM
Building on Acura's long history of advancing the science of automotive handling stability and control, the 3.5 RL comes standard with a state-of-the-art Vehicle Stability Assist (VSA) system. Developed in cooperation with Bosch, this four-channel system orchestrates the throttle and each of the RL's four disc brakes independently to seamlessly integrate traction control, anti-lock braking and stability enhancement processes under widely divergent road and driving conditions.

By monitoring input from six vehicle sensors, the VSA can calculate a predicted range of vehicle response while constantly monitoring the vehicle's actual response and the driver's control inputs. If the actual response is outside of the predicted response range -- as when cornering forces exceed the tire's performance, for example, VSA automatically intervenes with corrective action. In the case of oversteer during hard cornering (which might lead to spin), VSA applies braking to the outside front or rear wheel to help counter the unintended yawing tendency. On the other hand, if understeer becomes pronounced, VSA applies braking to the inside front or rear wheel to help turn the RL back onto the intended course.

Unlike some vehicle stability systems, which can seem intrusive to enthusiast drivers, the Acura VSA is calibrated to add to stability and predictability, without stifling the driving enjoyment of the RL's carefully engineered chassis and double wishbone suspension. An indicator light flashes on the instrument panel while the system is actively stabilizing the vehicle. A cockpit switch is provided to disable the vehicle stability and traction control aspects of the system while leaving the antilock braking system fully functional.

BRAKING SYSTEM
Large, power-assisted four-wheel disc brakes are standard, with ventilated rotors in front for minimal fade and excellent heat dissipation. By fine-tuning the leverage ratio of the brake pedal and the response characteristics of the power-brake vacuum diaphragm, the RL engineering team achieved reduced stopping distances while making brake response more linear and intuitive. Combined with the "low-creep" torque converter, these refinements also help make it easier to hold the RL at a stop.

ANTI-LOCK BRAKING SYSTEM
The 3.5 RL has a four-wheel Anti-Lock Braking System (ABS) that is integrated into the Vehicle Stability Assist (VSA) system. The ABS system operates in three-channel mode during straight-line braking (apportioning braking power to the front wheels independently and the rear wheels in tandem), and then automatically switches to four-channel mode when the VSA system senses high cornering forces. This allows the ABS system to take advantage of weight transfer to the outside of the turn during cornering and apply higher brake pressure to the outer rear wheel for braking performance.

The ABS enhances steering control during hard braking. Speed sensors at each wheel send signals to the ABS control module; if the system detects impending wheel lockup, it first holds, then reduces hydraulic pressure to the affected wheel, letting it regain traction before full braking resumes. The ABS function is also highly effective on split-friction surfaces, in which one side of the vehicle has significantly less traction than the other.

In the highly unlikely event of an ABS failure, a warning light is illuminated on the instrument panel. In such a case, the control module cancels the ABS function, allowing the standard braking system to operate normally. The system used in the RL is a design that weighs 1.3 kg less than the previous-generation ABS system.

TRACTION CONTROL
The traction control aspect of the Vehicle Stability Assist (VSA) system works just as seamlessly. When wheel slip is detected under acceleration, differential braking and engine controls are called into play to modulate the amount of power put to the ground. In situations where the drive wheels are on surfaces with different friction properties, such as when one drive wheel is in water while the other is on dry pavement, the system applies braking action to the wheel that's slipping, allowing the tire with better grip to move the vehicle. In addition to independent control of the front wheel brake, the system can also reduce total engine power output to keep wheel spin in check.

ROTARY-VALVE, VARIABLE POWER-ASSISTED, RACK-AND-PINION POWER STEERING
The speed-sensitive variable power-assisted rack-and-pinion steering uses a rotary valve that senses torque applied to the steering wheel and a vehicle speed sensor to vary power assist accordingly. The system adjusts steering assist for easy steering in parking-lot conditions and quick, precise steering feel at speed. The RL utilizes a magnesium-cast steering wheel for lighter steering feel, and a dynamic damper in the steering shaft for reduced wheel vibration.

WHEELS AND TIRES
The RL is equipped with P215/60R16 MXV4 Plus Michelin tires on 7.0 JJ x 16 cast-aluminum alloy wheels to maximize handling while minimizing road noise. The tires of the RL are of a special low-rolling-resistance design, which yields outstanding ride characteristics and improved fuel mileage while achieving excellent handling response and overall grip. The tires are an All-Season design, for enhanced traction on wet roads as well as on dry pavement.

2001 Acura 3.5 RL - Structure & Body

OVERVIEW
The 3.5 RL has a stamped-sheet-steel unit-body structure, designed to have a very high level of overall rigidity in both bending and torsion. The highly rigid structure was developed using a Cray supercomputer running the NASTRAN finite element-analysis program originally developed by NASA for building space vehicles. The chassis was made even more rigid by a rear support gusset, a large bulkhead bracket and rear crossbeam stabilizer.

The high rigidity of the 3.5 RL unit-body structure reduces noise and vibration in the passenger cabin, enhances handling precision and stability, creates excellent safety performance and increases overall durability. A high proportion of galvanized panels are used in the 3.5 RL structure and body panels for enhanced corrosion protection and overall longevity.

OVAL-SECTION FRONT TOWER BAR
Instead of a conventional tubular steel front brace between the firewall and the upper front-suspension locating points, the RL uses an oversized, oval-section tower bar brace, as well as a reinforcing plate that ties the firewall and front cowl section. This design increases rigidity as much as 12 times over a conventional round tube design, reducing cowl shake on rough roads and in spirited driving, while increasing steering precision.

FOAM-FILLED B- AND C-PILLARS
For reduced cabin-noise transmission, the B- and C-pillars are filled with a special heat-expanding rubberized foam material that expands to fill the hollow pillar during the baking cycles of the painting process.

HONEYCOMB FLOOR PANELS
Special lightweight honeycomb panels are used in the floor structure to increase rigidity and reduce noise and vibration. These panels are composed of a resin-impregnated fiber matrix bonded top and bottom to thin-gauge galvanized steel sheets.

BODY

OVERVIEW
The 3.5 RL body design is intended to impart a muscular stance and dynamic appearance while maintaining an enduring elegance and sophistication. The body of the 3.5 RL is significantly taller than previous Acura luxury sedans, for improved headroom, especially in the rear seats, and a more substantial exterior appearance. The 3.5 RL flanks are designed with high, relatively prominent "shoulder" lines, for a strong, masculine appearance, and the front grille/fender/bumper area is designed with a very clean, integrated configuration, giving a more massive, yet aerodynamically efficient look.

The 3.5 RL has a low coefficient of drag of 0.32 and a coefficient of lift of 0.102, resulting in greater high-speed stability and a very quiet, distraction-free interior environment.

PRECISE FIT AND FINISH
The RL is engineered and painstakingly assembled to have a level of fit and finish second to none in the luxury sedan class. Panels have been combined and integrated, wherever possible, to eliminate gaps and seams.

VISIBILITY
The tall, spacious-feeling greenhouse of the RL is designed to give the driver and passengers a clear, panoramic view of the road ahead and the surroundings to the sides and rear for enhanced safety. The driver's front, side and rear views are largely unobstructed, due to slim, yet highly rigid, roof pillars. The body is designed to give the driver a clear sense of the boundaries of the car, for more secure maneuvering and parking.

PAINT PROCESS AND CORROSION PROTECTION
The RL is built with a high proportion of galvanized steel panels, most of them galvanized on both sides for superior corrosion protection. All visible surfaces are protected by a 23-step, 4-coat, 4-bake paint process, with special antichip primer and special chip-resistant paint used in areas that are likely to be struck by stones or other debris. The paint process is so precise and exacting that personnel who work in the painting section of the factory wear special contamination-free clothing while working and are checked for colognes or other cosmetic chemicals that might cause the slightest contamination of the painting environment. Chassis panels are protected by corrosion-resistant undercoating material, and body cavities are injected with an oil-based anticorrosion wax that displaces moisture for even better protection.

CRYSTAL-CUT TAILLIGHT ASSEMBLY
The ultra-high quality appearance of the RL is enhanced by a special crystal structure cast into the inner surface of the RL rear outer-lens assembly.

SIDE-MIRROR AIR DEFLECTORS
As an example of the extraordinary lengths taken to reduce wind noise, the outside rearview mirrors are designed with a small wind deflector, or spoiler, that directs oncoming air down and away from the mirror assembly. By detaching the airflow under the mirror, the deflector reduces the pressure gradient between the air rushing around the mirror housing and the still air behind the mirror, eliminating a "whistling" effect there that has been identified as a cause of wind noise in the wind tunnel.

AUTO-OPEN POWER MOON ROOF
The RL includes an innovative power moon roof. The outer moon roof panel first tilts up, for increased ventilation, and then opens completely with one additional touch of the control button. Heat-rejecting privacy glass is used, and the moon roof is programmed to pause at the 130 mm position during closing to help ensure passenger safety.

UNDER-CHASSIS SPOILER
A special spoiler, located immediately behind the front bumper, has been developed to reduce airflow under the RL, thereby reducing the high-pressure air under the front of the body and diverting it to flow around the sides and over the top. This reduces drag and front-end lift and also reduces wind noise, helping to give the RL a remarkably quiet interior, even at high speeds.

2001 Acura 3.5 RL - Interior

OVERVIEW
A great deal of attention was given to the design, materials, comfort features and convenience amenities of the 3.5 RL interior, from major issues such as control location and passenger head, hip and shoulder room to smaller details such as extra-large beverage holders and a special compartment intended specifically for the driver's sunglasses. The overall design thrust was to give the interior a very open, relaxed ambience, much like the comfortable living room of an elegant, yet casual, contemporary luxury home.

MATERIALS
The leather seating surfaces that give the RL its luxurious look and feel are carefully hand-selected American hides that are tanned with an innovative process that helps the leather retain its soft, supple feel and resilient strength far longer than conventional automobile interior leather. The oils in conventional leather tend to slowly evaporate out of the hides, especially when the car is parked in the bright summer sun. This causes leather to prematurely age and dry out over time. It has another annoying side effect -- the oil that escapes from the leather is then deposited on the rear window and windshield glass when the interior cools, eventually causing a persistent and hard-to-remove "fogging" effect on the glass. The leather used in the RL is specially treated to resist this phenomenon; it reduces window fogging 90 percent better than conventional leather.

The center console of the RL features rich Tendo-camphor wood that has been carefully contoured, finished and preserved by a deep protective clear coat.

SEATING
The driver and front passenger seats are the products of extensive research and development. They are designed to absorb vibrations and bumps and to provide outstanding comfort without sacrificing the firm support needed in enthusiastic driving.

In testing, the RL seats decreased the upward force felt by test subjects by 50 percent over conventional seats; that is, the subjects felt the jarring of irregular road surfaces only half as strongly as with a conventional design.

Human factors research revealed that the human body has its own resonant frequency; that is, the vibration frequency at which the internal organs of the body pick up an outside vibration and resonate with it. If felt strongly, vibration in this frequency range is very unpleasant, and human test subjects generally gauge the vibration felt in a moving car on the level of vibration felt in this narrow range, between 5 and 10 Hz or cycles per second.

To damp out as much of this vibration frequency as possible, the configuration of the springs in the RL seat cushions were analyzed using the NASTRAN finite-element analysis program. Six different designs were tried before one was found that performed to Acura's exacting standards.

Other details in the seat design include gently rounded thigh bolsters at the front to avoid digging into the driver's and passenger's lower thighs. And the front lateral seam, which often runs across under the thighs, has been moved forward and down, eliminating this possible source of discomfort.

The front seats have even been designed to make rear-seat passengers more comfortable. The backs of the seats are concave, giving rear seat passengers nearly an inch more knee room. And the seat rail structure was designed to give rear-seat passengers nearly an inch more horizontal foot room, while the underside of the seat is carpeted to prevent shoe scuffs.

The driver's seat is eight-way power adjustable. It is linked by a memory system with the outside mirrors and electronic tilt and telescoping steering wheel, allowing one of two preset configurations to be accessed at the touch of a button. The front passenger's seat is four-way power adjustable. Both front seats are also heated.

The rear seats are designed and built to fit full-sized adults in total comfort as well. A fold-down center armrest incorporates its own dual beverage holder, and a pass-through to the trunk allows long objects to be carried without soiling or marring the interior.

INTERIOR COMFORT AND CONVENIENCE
The RL is the most lavishly equipped Acura ever built. Advances in soundproofing throughout the car make its interior by far the quietest in Acura history. Nearly everything is standard, including cruise control, individual reading lights, power windows, door locks, moon roof and remote keyless entry. The center console features an adjustable, two-position armrest and an illuminated storage area with a 12-volt accessory power outlet and tray designed to hold a cellular phone.

SPEED-SENSITIVE INTERMITTENT WIPER
The RL is equipped with an automatic, speed-sensitive intermittent wiper system that slows down the wipers when the RL is stopped or moving slowly and increases their speed when vehicle velocity increases. The wiper blades are specially designed to reduce noise while in operation.

AUTOMATIC HEADLIGHT SYSTEM
In the RL, a sensor at the front of the instrument panel senses outside illumination levels; when darkness occurs during automatic mode, the headlights, taillights and instrument panel lighting are automatically turned on for nighttime convenience. When the vehicle is parked at night, the lights are left on after the ignition switch is turned off, but go out automatically when the driver's door is opened.

INSTRUMENTS AND CONTROLS
Acura automobiles have always been known for their high level of ergonomic design and control harmony; the RL takes us to a whole new level of human engineering. The instrument panel is configured with a "trinocular" design. A large center speedometer and associated gauges monitor driving functions. A left-side, slightly smaller circle contains the tachometer while a symmetrical right-side circle includes the fuel gauge and less-used, yet important indicators. The instruments have large displays and are illuminated, even in daytime, for easy recognition. Much time and effort has gone into minimizing the attention needed to understand and monitor each particular system and to make each switch and control nearly as easy to use the first time as it will be after years of familiarity.

The engine's response to the throttle, for example, has been carefully analyzed and developed by fine-tuning the engine powerband, PGM-FI fuel injection system, transmission control unit and the physical layout and geometry of the throttle pedal itself. It has been developed to give a controlled feel that harmonizes, not only with the brake pedal and steering, but also with subjective human expectations of the effect a given push on the throttle will have on vehicle acceleration and speed. Every system has been optimized to give the driver what he or she asks for the first time, instead of forcing the driver to make a constant series of approximate control movements and subsequent corrections.

AUTOMATIC CLIMATE CONTROL
The RL is equipped with a state-of-the-art automatic climate control system and air conditioning system. The system is not only powerful in terms of cooling capacity and efficiency, but it is also extremely quiet, even when quickly cooling the interior on a hot Death Valley day. Even rear-seat passengers have personal control over the direction of heating or cooling air coming their way. Great pains have been taken to ensure cooling uniformity from front to rear, and an innovative subcondenser has been added to the A/C system, improving the efficiency of the unit substantially. In controlled testing, the A/C system cooled the interior from 100 degrees to 70 degrees Fahrenheit in 15 minutes--quicker than any other competitor in its class.

MICRON AIR FILTRATION
A state-of-the-art air-filtration system removes pollen and other contaminants from the interior environment. The filter element is so fine, it can trap all particles of 3 microns or larger, including almost all pollen and dust, and inhibits the passage of bacteria as small as 0.5 microns as well as some components of cigarette smoke and particulates in diesel exhaust. The filter has two layers: both are composed of felt-like, nonwoven fabric fibers, and one layer is electrostatically charged to help attract and trap even more dust and other airborne particles.

HEAT-REJECTING GLASS
Special solar-energy-absorbing, green-tinted glass is used in the RL, minimizing the effects of the hot sun on the interior and its occupants. This reduces the load on the climate control system for better cooling efficiency, delays the temperature rise in the interior when the vehicle is parked, and further protects the interior leather and other materials from the effects of solar radiation.

AUDIO SYSTEM
The Acura/Bose audio system for the RL is the most impressive ever designed for an Acura automobile. Developed and tuned by Bose Corporation specially for the RL, the music system is acoustically optimized to provide clear, authentic sound in any seating position of the interior and automatically compensate the balance of bass, treble and midrange for any volume level. It features an AM/FM tuner, cassette and a six-disc CD changer mounted in the trunk.

Eight speakers are used: two 2.5-inch tweeters mounted in the front doors, two 6.5-inch single-cone full-range speakers in the lower front door panels, two 5.25-inch full-range speakers, mounted in the rear-door panels and two 6 x 9-inch low-frequency drivers in the rear package shelf.

From the easily accessible, dash-mounted control unit, audio output is sent to the auxiliary power amplifier unit located in the trunk. Separate amplifiers are provided inside the unit for each of the six individual front speakers. Each tweeter has a 12.5-watt amplifier while each of the four full-range speakers has its own 25-watt amplifier and the two rear speakers, which act in concert as subwoofers, share a 100-watt amplifier. Total music system power is 225 watts.

The antenna for the various receiver systems are all built into the rear window. These include the AM/FM antenna and the antenna for the radio-based keyless entry system. The elimination of the antenna mast lessens complexity and reduces wind noise for the rear-seat passengers.

ACURA NAVIGATION SYSTEM
The Acura Navigation System is the only factory-installed option available on the fully equipped 2001 3.5 RL. It features a seven-inch matte-finish touch-screen that resists fingerprinting and is easy to read. Smart logic allows you to type in your destination with only a few keystrokes, and route calculation time is very fast. You can also preprogram a route with up to five destinations, or have the moving map display icons for gas stations, restaurants or ATMs. And with a Digital Video Disc (DVD) on-board database, the entire continental United States is contained on a single disc.

The Acura Navigation System unit uses Global Positioning System (GPS) data received from satellites, as well as its own inertial guidance system, to precisely pinpoint the location* and velocity of the car. When asked to guide the driver from one location to another, the system provides both audio and visual cues, helping the driver to find the proper destination quickly and easily and with minimal distraction. Verbal instructions such as, "Keep right" or "Next exit on the right" give the driver the basic direction, and a visual LCD moving map with a directional arrow, located high on the center console, provides detailed information on street names, turning instructions and driving distances. The navigation system also provides information and directions to 3.7 million local restaurants, theaters and points of interest.

The seven-inch, color LCD display has a picture-in-picture capability, so you can see the "big picture" map and get detailed turning instructions simultaneously. The system will also display your current position coordinates at any time, and a balloon function instantly shows the address of any location you select on the map. You can also search for a selected point of interest simply by inputting its phone number. The voice guidance control has 11 different volume settings and automatically mutes the audio entertainment system front speakers momentarily when direction commands are given.

SECURITY/IMMOBILIZER SYSTEM
A remote keyless entry system is standard on the RL. The keyless entry system is radio-controlled -- this gives much better range than a conventional infrared system, allowing the driver to unlock the RL or activate the "panic button" antitheft function while still a considerable distance from the car. A special electronically coded key prevents the car from being started, even if a mechanical duplicate of the proper key shape is used. A transponder, built into the key, signals the immobilizer control unit the key is genuine. If the car is hot-wired, or an unauthorized key is used, it simply will not start. This system is a substantial deterrent to theft.

* Major metropolitan areas are mapped in detail by the system.

2001 Acura 3.5 RL - Safety

OVERVIEW
The 3.5 RL is not just the most luxurious and impressive Acura sedan ever built it also incorporates state-of-the-art safety engineering. Advances in strength and rigidity of the unit-body structure, as well as innovations in side-impact protection and airbag technology make the 3.5 RL as safe and secure as it is comfortable and gratifying to drive. And, for increased driver control, standard equipment includes an Anti-lock Braking System (ABS) and a Vehicle Stability Assist (VSA) system that incorporates traction control functions.

DUAL AIR BAGS AND AUTOMATIC SEAT BELT PRETENSIONERS
Three-point lap-and-shoulder belts are provided at all seating positions. A dual front airbag Supplemental Restraint System (SRS) helps to protect the driver and front passenger in a moderate to severe frontal impact, and automatic seat belt pretensioners help keep front passengers firmly in position in order to take advantage of the protection afforded by the air bag system.

DUAL-STAGE PASSENGER AIR BAG
To enhance the protection of the front seat passenger during a variety of frontal impact collisions, varying air bag deployment power is used in the RL. The Honda R&D designed system, which uses a dual-stage inflator, is the first such design ever to be used on an automobile and automatically adjusts the deployment of the front passenger SRS airbag based on the severity of the crash. During a slower speed collision, the dual-stage inflator system for the dash-mounted air bag is triggered in sequence, resulting in slower overall air bag deployment with less initial force. During a higher speed collision, both inflators operate simultaneously for full immediate inflation, to correspond with the greater impact force.

The airbag system logic also controls the operation of the seatbelt pretensioners, which automatically tighten the seatbelts during a collision to help hold occupants in place.

SIDE AIR BAG SYSTEM
The RL features seat-mounted side air bags for the driver and front seat passenger. The front passenger seat is equipped with an innovative system designed to disable side air bag deployment and prevent injury to a small child or small statured adult if he or she leans into the side air bag deployment path. A series of seven sensors in the passenger seatback determine the height and position of the occupant to assist the system in determining if it is safe to deploy the side air bag. If the person is in the deployment path of the side air bag, the system will prevent the side air bag from inflating. When the child returns to an upright seating position, the side airbag will reactivate so it can deploy and protect the person in a side impact.

SIDE IMPACT PROTECTION
Dual anti-intrusion beams in the front doors, as well as expanded polypropylene hip and shoulder pads, built into the door structure, help protect front- and rear-seat passengers in a possible lateral collision. Anti-intrusion door beams are also used in the rear doors. And innovative, expanded polystyrene liners, installed above the front doors and inside the A-pillars, help give front-seat passengers added head protection in side-impact situations.

REAR CHILD SEAT TETHER ANCHORS
To allow a child seat to be securely positioned in any of the back seat positions, rear child seat tether anchors are standard in the RL.

FRONT AND REAR CRUMPLE ZONES
The RL's structure is designed to deform progressively in both front and rear impacts, letting the front and rear sections absorb the energy of a collision while helping to keep the highly rigid center-passenger section intact. Straight frame rails, front and rear, give the structure the strength necessary to help the RL withstand offset collisions at either end, with reduced possibilities for passenger injury.

EMERGENCY TRUNK RELEASE
The RL is equipped with an emergency trunk release located inside the trunk.

XENON HIGH INTENSITY DISCHARGE (HID) HEADLIGHTS
The RL features Xenon High-Intensity Discharge (HID) headlights with double the total illuminating power of conventional halogen headlamps, enhancing visibility and active safety performance. Standard fog lamps are integrated into the bumper fascia for improved performance in combination with the HID headlights. The HID headlight bulbs also last twice as long as halogen bulbs and require less energy to operate.