Acura NSX First-generation (NA1, NA2; 1990–2005)
The first generation Honda NSX, marketed in North America and Hong Kong as the Acura NSX, is a 2-seater, mid-engined sports car that was manufactured by Honda Motor Company in Japan from 1990 to 2005.
Acura NSX First-Generation
Around 1984, Honda engineers began experimenting with different engine and chassis layouts to test viability for future products. One of the test mules was a Honda City that had been cut in half, with the engine installed behind the driver’s seat and powering the rear wheels. Although the project was not developed any further, many of the engineers were inspired by the exciting laps around the company parking lot in the mid-engined City. This experience, in part, convinced Honda leadership that the company should consider developing a pure sports car. As a result, in 1984, Honda commissioned the Italian car styling house Pininfarina to design the concept car HP-X (Honda Pininfarina eXperimental), which had a C20A 2.0 L V6 engine in a mid-mounted configuration. After Honda committed to a sports car project, the company management informed the engineers working on the project that the new car would have to be as fast as anything coming from Italy and Germany. The HP-X concept car evolved into a prototype known as NS-X, which stood for “New”, “Sportscar” “eXperimental”. The prototype and eventual production model—which was marketed as the Acura NSX — were designed by a team led by Honda Chief Designer, Masahito Nakano, and Executive Chief Engineer, Shigeru Uehara (who were subsequently placed in charge of the S2000 project).
The original performance target for Honda’s new sports car was the Ferrari 328 (and later, the 348) as the design neared completion. Honda intended its sports car to meet or exceed the performance of the Ferrari, while offering superior reliability and a lower price. For this reason, the 2.0 L V6 engine utilised in the HP-X was shelved and ultimately replaced with a significantly more powerful 3.0 L VTEC V6 engine. Over the course of development of the Acura NSX, many engines were used, ranging from the 2.7-litre single overhead camshaft V6 engine from the Honda Legend/Honda Coupé to the 3.0-litre single overhead camshaft V6 engine, used subsequently in 15 test mules. Honda eventually settled on a non-VTEC, 3.0-liter double overhead camshaft 24-valve V6 engine selected for the production model. This engine generated a maximum power output of about 250 hp (186 kW; 253 PS) and 282 N⋅m (208 lb⋅ft) of torque, with a redline of 7,300 rpm. However, at the same time, Honda was working on its revolutionary VTEC variable valve timing system, with plans to release it on the company’s home-market 4-cylinder Integra. Honda’s then-president Tadashi Kume, himself a highly-skilled and respected engine designer, questioned the NS-X designers’ logic in foregoing the VTEC system for Honda’s new flagship sports car, while it was being used on the lower-market Integra. As a result, the engine was redesigned very late in the development process “to achieve the desired levels of performance and durability”; Honda designed a new cylinder block with 6-bolt main caps and larger cylinder heads to contain the complex VTEC mechanism. Innovative connecting rods made from a titanium alloy were used to lower reciprocating weight, while increasing overall rod-strength—something which increased the engine’s maximum rpm by 700, resulting in a final redline of 8,000 rpm. A consequence of this last-minute engine change was that the new C30A engine was too large to fit in the NS-X’s engine bay, which had been carefully sized for the smaller heads of the non-VTEC DOHC 3.0 liter engine. As a result, the engineers were forced to tilt the entire engine backward approximately 5 degrees- a characteristic that continued all the way to the NSX’s final production in 2005.
The exterior design had been specifically researched by Uehara after studying the 360-degree visibility inside an F-16 fighter jet’s cockpit. Thematically, the F-16 came into play in the exterior design as well as establishing the conceptual goals of the Acura NSX. In the F-16 and other high performance air-crafts such as unlimited hydroplanes along with open-wheel race cars, the cockpit is located far forward and in front of the power plant. This “cab-forward” layout was chosen to optimize visibility while the long tail design enhanced high speed directional stability. The Acura NSX was designed to showcase several automotive technologies, many derived from Honda’s F1 motor-sports program.
The Acura NSX was the first production car to feature an all-aluminium semi-monocoque, incorporating a revolutionary extruded aluminium alloy frame and suspension components. The use of aluminium saved nearly 200 kg (441 lb) of weight over the use of steel in the body alone, while the aluminium suspension arms saved an additional 20 kg (44 lb); a suspension compliance pivot helped maintain wheel alignment changes at a near zero value throughout the suspension cycle. Other notable features included an independent, 4-channel anti-lock brake system; an electric power steering system; Honda’s proprietary VTEC variable valve timing system and in 1995, the first electronic throttle control fitted in Honda production car.
With a robust motorsports division, Honda had significant development resources at its disposal and made extensive use of them. Respected Japanese Formula One driver Satoru Nakajima, for example, was involved with Honda in the NSX’s early on-track development at Suzuka race circuit, where he performed many endurance distance duties related to chassis tuning. Brazilian Formula One World Champion Ayrton Senna, who won many races in Formula One with Honda before his death in 1994, was considered Honda’s main innovator in convincing the company to stiffen the NSX’s chassis further after initially testing the car at Honda’s Suzuka GP circuit in Japan. Senna further helped refine the original NSX’s suspension tuning and handling by spending a whole day test driving prototypes and reporting his findings to Honda engineers after each of the day’s five testing sessions. Senna also tested the Acura NSX at the Nürburgring and other race tracks. As a result of Senna’s input, Honda took the NS-X prototype to the Nurburgring to tune the chassis stiffness. Over the course of several months, the chassis was refined in a painstaking process: Nakajima would drive a lap on the circuit and then discuss with the Honda engineers where he felt flex in the chassis. The engineers would hand-weld aluminum braces in the area they believed would fix the issue and send the driver back out to confirm. This process was repeated over and over, with the data results sent directly to Honda headquarters in Japan, where it was fed into a Cray supercomputer and translated into reinforcements in the production aluminum monocoque. As a result of this process, the NS-X chassis stiffness increased by over 50% with only a small increase in weight. The suspension development program was similarly far-ranging and took place at the Tochigi Proving Grounds, the Suzuka circuit, the 179-turn Nürburgring Course in Germany, HPCC, and Honda’s newest test track in Takasu, Hokkaido. Honda automobile dealer Bobby Rahal (two-time CART PPG Cup and 1986 Indianapolis 500 champion) also participated in the car’s development.
Transversely mounted 3-liter Honda C30A V6 engine
Official launch and production
The Acura NSX made its first public appearances in 1989, at the Chicago Auto Show in February and at the Tokyo Motor Show in October of that year, receiving positive reviews. Honda revised the car’s name from NS-X to NSX before commencement of production and sales. The Acura NSX went on sale in Japan in 1990 at Honda Verno dealership sales channels, supplanting the Prelude as the flagship model. The Acura NSX was sold under Honda’s Acura luxury brand starting in November 1990 in North America and Hong Kong.
Upon its official debut, the Acura NSX design concept showcased Honda’s technology, measuring only 1,170 mm (46 in) in height, making it only 141.3 mm (5.56 in) taller than the Ford GT40, a GT racing car designed and funded solely to win at LeMans. The Japanese car maker’s race track innovations and competitive history were further exemplified on the road by the NSX’s ultra-rigid and ultra-light all aluminium monocoque chassis along with front and rear double wishbone suspension, with forged control arms connected to forged alloy wheels. The car additionally boasted the world’s first production car engine with titanium connecting rods, forged pistons, and ultra high-revving capabilities – the redline was at 8,300 rpm – all traits usually associated with track and race engineered cars. The NSX’s exterior had a dedicated 23-step paint process, including an aircraft type chromate coating designed for chemically protecting the aluminium bodywork and a waterborne paint for the base coat to achieve a clearer, more vivid top color and a smoother surface finish.
The car’s chassis rigidity and cornering/handling capabilities were the results of Formula One driver Ayrton Senna’s consultation with NSX’s chief engineers while testing the Acura NSX prototype at Honda’s Suzuka Circuit during its final development. The Acura NSX was initially assembled at the purpose-built Takanezawa R&D Plant in Tochigi from 1989 to early 2004, when it was moved to Suzuka Plant for the remainder of its production life. The cars were assembled by approximately 200 of Honda’s highest-skilled and most experienced personnel, a team of hand-picked staff with a minimum of ten years assembly experience employed from various other Honda facilities to run the NSX operation.
Production of the first generation of the Acura NSX ended on November 30, 2005. Sales in the United States and Canada ended in 2005 and 2000, respectively.
As of the end of June 2005, the Acura NSX achieved total worldwide sales of more than 18,000 units in over 15 years.
Acura NSX rear view
Acura NSX-R (1992)
While the Acura NSX always was intended to be a world-class exotic sports car, engineers did make some compromises in order to strike a suitable balance between raw performance and daily driveability. For those Acura NSX customers seeking a no-compromise racing experience, Honda Motor Company decided in 1992 to produce a version of the Acura NSX specifically modified for superior track performance at the expense of customary creature comforts. Thus, the Acura NSX Type R (or Acura NSX-R) was born. Honda Motor Company chose to use its moniker of Type R to designate the Acura NSX-R’s race-oriented capabilities.
Honda Motor Company engineers started with a base Acura NSX coupé and embarked on an aggressive program of weight reduction. Sound deadening, the audio system, spare tyre, air conditioning system and traction control along with some of the electrical equipment were removed. The power leather seats were exchanged for lightweight carbon-kevlar racing seats made by Recaro for Honda. However, electric windows and fore/aft electric seat adjusters stayed. The stock forged alloy wheels were replaced with lighter forged aluminium wheels produced by Enkei, which reduced the car’s unsprung weight. The standard leather shift knob was replaced with a sculpted titanium piece. Overall, Honda Motor Company managed to reduce approximately 120 kg (265 lb) of weight as compared to the standard Acura NSX, resulting in the Acura NSX-R‘s final weight of 1,230 kg (2,712 lb).
As found by the automotive press such as Car and Driver in their September 1997 issue’s comparison of “Best Handling Car for more than $30K”, the Acura NSX, due to its mid-engine layout and rear-end link travel, was susceptible to sudden oversteer during certain cornering maneuvers. While this condition rarely occurred during normal driving conditions, it was much more prevalent on race tracks where speeds were much higher. To address the problem and improve the Acura NSX-R’s cornering stability at the limit, Honda Motor Company added one aluminium bracket under the front battery tray and added one bracket in front of the front radiator to add more chassis rigidity replacing the entire suspension system with a more track oriented unit, featuring a stiffer front sway bar, stiffer suspension bushings, stiffer coil springs and stiffer dampers.
The standard Acura NSX has a somewhat rearward bias in its spring and bar rates, where the rear was relatively quite stiff versus the front. This means that the lateral load transfer distribution, or the amount of load that is transferred across the front axle versus the rear while cornering, is rather rear biased. This can make the car quite lively and easy to rotate at low speed, but during high speed cornering, this effect becomes more pronounced and could be a handful to manage. To reduce the tendency to oversteer, Honda Motor Company fitted softer rear tyres on the Acura NSX. For the Acura NSX-R, Honda Motor Company reversed the spring bias, placing stiffer springs on the front suspension along with stiffer front sway bar. This shifted the load transfer stiffness balance farther forward, resulting in more rear grip at the expense of front grip; this had the effect of decreasing the oversteer tendency of the car, making it much more stable while cornering at high speeds. Overall, the Acura NSX-R utilizes a much stiffer front sway bar along with stiffer springs than the standard Acura NSX (21.0 mm x 2.6 mm front sway bar: front 3.0 kg/mm, rear 4.0 kg/mm for the Acura NSX versus front 8.0 kg/mm, rear 5.7 kg/mm for the Acura NSX-R).
Honda Motor Company also increased the final drive ratio to a 4.235:1 in place of the 4.06:1, which resulted in faster gear changes. This change improved acceleration at the expense of top speed, and a higher locking limited-slip differential was installed. Also, the Acura NSX-R’s 3.0-liter engine had a blueprinted and balanced crankshaft assembly which is exactly the same labour-intensive high precision process done for Honda racing car engines built by highly qualified engine technicians.
Beginning in late November 1992, Honda Motor Company produced a limited number of 483 Acura NSX-R variants exclusively for the Japanese domestic market (JDM). Factory optional equipment such as air conditioning, Bose stereo system, carbon fibre interior trim on the centre console as well as the doors and larger wheels painted in Championship White (16-inches at the front and 17-inches at the rear) were available for a hefty premium. Production of the Acura NSX-R ended in September, 1995.
1997 Acura NSX (JDM) pre-facelift
Acura NSX-T (1995)
Beginning in 1995, the Acura NSX-T with a removable targa top in black colour was introduced in Japan as a special order option and in North America in March 1995. The Acura NSX-T largely replaced the standard coupé entirely in North America as the only version available post 1994 and all Acura NSXs thereafter were available in targa bodystyle, with two notable exceptions: the Zanardi Special Edition Acura NSX in 1999; and a handful of special order post-1997/pre-2002 3.2-liter base model cars, both of which retained the original hardtop configuration. The European market continued to offer both body styles. The removable roof resulted in decreased chassis rigidity and Honda Motor Company added about 100 pounds (45 kg) of structural reinforcements to compensate, including significantly thicker frame sidesill rocker panels (the body component which contributes most to the chassis’s rigidity), bulkheads, roof pillars and the addition of new front/rear bulkhead and floorpan crossmembers. The targa models, manufactured for the rest of the NSX’s production run through 2005, sacrificed weight and some of the original coupé’s chassis rigidity in return for an open cockpit driving experience. In addition to this major change, all subsequent Acura NSX-Ts (1995–2001) had smaller-diameter front sway bars, slightly stiffer front springs, softer rear springs and firmer shock-dampers to improve ride comfort and tyre wear while reducing the tendency towards oversteer common in mid-engined vehicles. The small handful of special ordered, base model “hardtop” Acura NSX‘s from 1997–2001, still retained the original black roof. All other roofs post 1995 were now body-coloured instead of black, although in Japan, the two-tone black roof/body colour was still available as an optional feature. A lighter version of the variable ratio electric assisted power steering rack, previously found exclusively in the cars equipped with the automatic transmission, became standard on all models. Starting in 1995, the 5-speed transmission’s second gear ratio was lowered by 4.2% to improve driveability and provide better response and automatic transmissions received an optional Formula One-inspired Sport Shift with a unique steering column mounted electronic shifter. Manual transmission cars received an improved Torque Reactive limited-slip differential – when combined with a new Throttle-By-Wire system, increased corner exit speeds by 10%. Other innovations beginning in 1995 included a new and lighter exhaust system and muffler configuration for greater efficiency and lower emissions, an OBD-II onboard diagnostic system, improvements in the Traction Control System (TCS) and newly developed fuel injectors.
1995 Acura NSX-T
1997 performance upgrades
In 1997, Honda Motor Company introduced the Acura NSX‘s biggest performance upgrade for all of its worldwide markets. Engine displacement was increased from 3.0 Liter to 3.2 Liter using a thinner fiber-reinforced metal (FRM) cylinder liner. The exhaust manifold was reconfigured and made of stainless steel header pipes rather than a cast-iron manifold for improved performance and lighter weight. The increased flow from this new configuration was a key contributor to the 20 additional horsepower drawn from the new engine. This revised 3.2 Liter C32B engine provided a substantial increase to power output: from 274 PS (202 kW; 270 hp) to 294 PS (216 kW; 290 hp) while torque increased from 285 N⋅m (210 lb⋅ft) to 305 N⋅m (225 lb⋅ft) (for cars equipped with manual transmission only). The net result increased the power to weight ratio of the Acura NSX by 7%. The 4-speed automatic model retained its 3.0 Liter engine and 252 hp power output. Another big change was the adoption of a 6-speed manual transmission with closer gear ratios and the addition of 3rd to 4th gear dual cone synchronizers. To handle the new engine’s added torque and power the small diameter twin-disc clutch system of the 5-speed was replaced by a dual-mass low-inertia single disc clutch system. To offset the weight increase of the new 6-speed transmission and larger brake rotors, which had increased diameter from 11.1 in (281.9 mm) to 11.732 inches (298.0 mm), key body parts were made with a new aluminium alloy that was up to 50% stronger allowing the thinner lighter material to be used in the doors, fenders, and front and rear deck lids without any sacrifice of strength and rigidity. Using this hi-strength alloy the net curb weight increase, despite adding many improvements, was only 10 kg (22 lb). Other notable changes included a keyless entry system, vehicle immobilizer system and inclusion of electric power steering on the hardtop coupe trims. The combination of slightly increased power and torque and a new 6-speed transmission, with ratios optimised to improve straight-line acceleration, produced better performance numbers over previous models than the modest increases would suggest. Motor Trend and Road & Track’s (February 97) tests of the 3.2 Liter 6-speed equipped Acura NSX-T (Targa) resulted in 0–60 mph acceleration times of 4.8 and 5.0 seconds and quarter-mile times of 13.3 and 13.5 seconds respectively. 0–60 mph times dropped to as low as 4.5 seconds in the coupé 3.2 Liter variant as recorded by Car and Driver in their August 1998 0–150–0 issue. The Acura NSX proved to be the fastest ever tested in North America when tested by the magazine. When Car and Driver tested the 1999 Zanardi special edition coupé a year later it resulted in a 0–60 mph acceleration time of 4.8 seconds and a 13.2 second quarter-mile time. Although magazine tests for the later face-lift Acura NSX were rare, Honda Motor Company apparently kept improving the engine as Sports and Exotic Car magazine noted in a farewell article on a 2005 Acura NSX-T and recorded a 0–60 mph acceleration time of 4.7 seconds and a 13.1 second quarter-mile time.
Acura NSX Type-R
1997 Acura NSX Type S (JDM)
Along with the engine displacement increase in 1997, Japan exclusively received the Acura NSX Type S. The Type S was intended to be a “winding road” optimized trim option and incorporated several weight-reducing features to improve performance: Titanium Shift Knob, MOMO Zagato-style steering wheel, BBS lightweight aluminium wheels(16″/17″) and a lightweight rear spoiler. The Type S also carried over several weight reducing features from the earlier Acura NSX-R: Recaro full bucket carbon-kevlar Alcantara/leather seats, mesh design engine cover, single-pane rear glass, manual rack and pinion steering and a lightweight battery. Unlike the Acura NSX-R, which used the black roof from the original Acura NSX, the Type S was offered with a body-color matching roof. Overall, the weight reduction efforts resulted in a curb weight of 1,320 kg (2,910 lb) for the Type S, which was some 45 kg (99 lb) lighter than the standard Acura NSX coupe. However, due to its premium trim level, customers could add options like navigation, electric power steering, HID xenon headlights and fog lights, partially negating some of the weight savings. Indeed, the Acura NSX Type S was the most expensive Acura NSX trim model available in 1997 at ¥10,357,000 (or $85,000 in 1997 dollars). Honda Motor Company also extensively revised the Type S suspension to incorporate much stiffer front dampers and a thicker rear sway bar. Honda Motor Company produced 209 Acura NSX Type S units between 1997 and 2001.
1997 Acura NSX-T
1997 Acura NSX Type S-Zero (JDM)
Along with the Type S, Honda Motor Company offered the Acura NSX Type S-Zero for customers who desired a track-day weekend car and who would normally purchase the now-discontinued Acura NSX-R. Designated “Zero” to indicate extreme weight reduction, the S-Zero is a more circuit-oriented version of the standard Type S. Handling was improved for the circuit by using the NA1 NSX-R suspension but retaining the Type S’ thicker 19.1 mm rear sway bar. The S-Zero also ditched the dual mass flywheel clutch and reverted back to the lighter, more direct dual-disc clutch from the original Acura NSX 5-speed transmission. Unlike the standard Type S, the S-Zero did not offer cruise control, stereo, power door locks, airbags, traction control, power steering, fog lights or a navigation system. Air conditioning, however, was the only option. Much of the sound deadening material was also removed to reduce weight. All of this weight reduction resulted in making the S-Zero 50 kg (110 lb) lighter than the Type S, weighing in at 1,270 kg (2,800 lb). Combining extreme weight reduction with the power and performance improvements of the new 3.2 Liter engine and 6-speed transmission, the S-Zero could lap the Suzuka circuit 1.5 seconds faster than the already formidable Acura NSX-R. Only 30 Acura NSX Type-S Zeros were produced between 1997 and 2001, making it the rarest version of the Acura NSX next to the five homologation special Acura NSX-R GT cars.
1999 Acura NSX "Alex Zanardi" edition (USA)
Produced exclusively for the United States, the Acura NSX Alex Zanardi Edition was introduced in 1999 to commemorate Alex Zanardi’s two back-to-back CART IndyCar championship wins for Honda in 1997 and 1998. Only 51 examples were built, and they were available only in New Formula Red to reflect the color of the winning car Zanardi drove for Chip Ganassi Racing.
The Zanardi Edition was similar to the Japanese market Acura NSX Type S. Visible differences between the Zanardi Edition and the Type S were the Zanardi’s left-hand drive configuration, black leather and suede seats with red stitching, airbag-equipped Acura steering wheel, and a brushed-aluminium plaque with an engraved Acura logo, Zanardi’s signature, and a serial number on the rear bulkhead. Total vehicle weight was reduced by 149 pounds (68 kg) as compared to the Acura NSX-T, through the use of a fixed roof, lighter rear spoiler, single pane rear glass, lightweight BBS alloy wheels, a lighter battery, and a manual rack-and-pinion steering system in place of the electric power steering.
Zanardi Number 0 was a press car that also appeared in auto shows across the country. In a handling test in Road & Track’s June 1999 issue, the Zanardi NSX placed second against the Dodge Viper GTS-R, Lotus Esprit, Porsche 911 Carrera 4, Ferrari F355 Spider, and Chevrolet Corvette C5 Coupé. The car was also featured in Car and Driver’s July 1999 issue before being sold to a private individual.
Zanardi Number 1 belongs to Zanardi himself and was not given a North American VIN. The car is rumored to have been modified by Honda with hand-activated throttle, braking, and shifting mechanisms to accommodate Zanardi’s loss of both legs resulting from his Lausitzring crash in 2001.
Zanardi numbers 2 through 50 were sold to the general public through dealers.
Acura NSX 2002 post-facelift
2002 Acura NSX facelift
In December 2001, the Acura NSX received a facelift in order to keep the car more modern looking like its competitors. The original pop-up headlamps were replaced with fixed xenon HID headlamp units, along with slightly wider rear tyres to complement a revised suspension. The gauge faces changed to a blue shade and, in 2004, the shift knob was changed to a weighted metal ball from the prior leather-wrapped plastic. Front spring rates were increased from 3.2 kg/m to 3.5 kg/m, rear spring rates were increased from 3.8 kg/m to 4.0 kg/m and the diameter of the rear stabilizer bar increased from 17.5 mm to 19.1 mm with a 2.3 mm wall thickness. The tail light housings were also revised along with the rear spoiler, which now included a small flap on the deck lid. The rear valence was lowered and wrapped around the car to revised side skirts. These changes made the car appear to sit lower on the ground.
Due to the changes in design, the drag coefficient slightly dropped to 0.30 which contributed to improvement in acceleration and top speed with an improvement in the 0–201 km/h (0–125 mph) acceleration time by 0.2 seconds and an increased top speed of 282 km/h (175 mph).
The hardtop coupé was no longer available in North America from 2002 onwards, but coupes could still be ordered in Japan. The Acura NSX Type S also received the same cosmetic updates, with a slight revision to the suspension replacing the linear rate springs with progressive springs. The S-Zero trim model was cancelled due to the re-introduction of the NSX-R. The Acura NSX was now made available in a number of exterior colours with either a matching or black interior to provide a number of possible colour combinations. A 4-speed automatic transmission with manual-type shift option also became available.
Acura NSX-R Mid-year 2002 post-facelift
Acura NSX-R facelift (2002)
A second iteration of the Acura NSX-R was unveiled in 2002, again exclusively in Japan. As with the first Acura NSX-R, weight reduction was the primary focus for performance enhancement. The Acura NSX-R was again based on the coupé, due to its lighter weight and more rigid construction. Carbon fibre was used to a large extent throughout the body components to reduce weight, including a larger and more aggressive rear spoiler, vented hood and deck lid. The vented hood was said to be the largest one-piece carbon-fiber hood used on a production road car. Additionally, the original Acura NSX-R’s weight reduction techniques were repeated, including deletion of the audio system, sound insulation and air conditioning. Furthermore, the power steering was removed. A single-pane rear divider was again used, as were Recaro carbon-kevlar racing seats. Finally, larger yet lighter wheels resulted in a total weight reduction of almost 100 kg (220 lb) to 1,270 kg (2,800 lb).
The 3.2 Liter DOHC V6 engine received special attention as well. Each car’s engine was hand assembled by a skilled technician using techniques normally reserved for racing programs. Components of the rotating assembly (pistons, rods and crankshaft) were precision weighed and matched so that all components fell within a very small tolerance of weight differential. Then, the entire rotating assembly was balanced to a level of accuracy, ten times than that of a typical Acura NSX engine. This balancing and blueprinting process significantly reduced parasitic loss of power due to inertial imbalance, resulting in a more powerful, free-revving powerplant with an excellent throttle response. Officially, Honda maintains that the power output of the 2002 NSX-R’s engine is rated at 290 hp (220 kW), which is identical to the standard Acura NSX. The automotive press, however, has long speculated that the true output of the engine is higher.
Creating the impression of increased power, the accelerator was re-tuned, becoming much more sensitive to movement, particularly at the beginning of the pedal’s new shorter stroke. This, coupled with the harsh suspension, makes it difficult for the driver to drive smoothly at low speeds on streets with even slight bumps. The lack of power steering has also been noted by drivers as making the car tiring and hard to steer at low speed.
The result of Honda’s second Acura NSX-R effort was a vehicle that could challenge the latest sports car models on the track, despite having a base design that was more than 15 years old. For example, noted Japanese race and test driver Motoharu Kurosawa piloted a 2002 NSX-R around the Nürburgring road course in 7:56, a time equal to a Ferrari 360 Challenge Stradale. The Acura NSX-R accomplished this feat despite being out-powered by the Ferrari by over 100 bhp (75 kW).
Acura NSX-R Mid-year 2002 rear-view
Acura NSX-R GT (JDM)
After the launch of the facelifted Acura NSX-R, Honda Motor Company developed a more agile, more responsive, and quicker limited edition Acura NSX-R called the Acura NSX-R GT. The Acura NSX-R GT was created by Honda solely to comply with the Super GT production-based race car homologation requirements. As JGTC rules required at least five production cars for any race car version to compete, as a result the Acura NSX-R GT was limited to a production run of only five cars.
The differences between the second generation Acura NSX-R and the Acura NSX-R GT are not fully known. One clear difference is the addition of a non-functional snorkel attached to the roof of the car. In the JGTC NSX race cars however, this snorkel is fully functional, feeding outside air to an individual throttle body intake plenum. The Acura NSX-R GT also has a lowered suspension and widened body. More aggressive aerodynamic components such as an extended front spoiler lip and large rear diffuser were used as well. It was also speculated that the Acura NSX-R GT incorporates more weight savings over the NSX-R. Honda never advertised what, if any, changes were made to the 3.2 Liter DOHC V6 for the Acura NSX-R GT.
24 Hours of Le Mans
The Acura NSX GT1 and GT2 Le Mans race cars started out as factory Acura NSX-R shells. 11 of these shells were shipped to TC Prototypes in England, where they were extensively re-worked in preparation for race duty. A custom dry carbon fiber tub was bonded to the interior, and additional dry carbon fiber pieces were used to reinforce the already stiff chassis. The suspension was completely replaced by a custom setup with race dampers and aluminum control arms mated to center-nut style wheel hubs. TC added wide body fenders to accommodate the wider race tires and improve downforce.
The C30A engine was extensively revised to include a dry sump oiling system, larger cams, inconel exhaust headers and, for the GT2 cars, a massive carbon fiber intake plenum with six individual throttle bodies. The GT1 engines received a turbocharger with a custom dual-plenum aluminum manifold. Using bespoke engine management, the GT2 engines produced nearly 400 bhp (a 130 bhp increase from the production version) and the turbocharged GT1 engines produced over 600 bhp, making them the most powerful engines Honda ever used in the Acura NSX. Both engines were mated to a Hewland 6-speed sequential transmission, the use of which would later plague the cars in the Le Mans race.
The Acura NSX made three appearances at the 24 Hours of Le Mans, in 1994, 1995, and 1996.
Three Honda NSXs were entered in the 1994 24 Hours of Le Mans. Cars numbers 46, 47 and 48 were prepared and run by team Kremer Racing Honda, with Team Kunimitsu assisting and driving the number 47 car. All were in the GT2 class, and all completed the race, but placed 14th, 16th and 18th.
Three Honda NSXs were entered in the 1995 24 Hours of Le Mans. Honda’s factory team brought two NSXs which were entered in the GT1 class numbered 46 (turbocharged) and 47 (naturally aspirated). Team Kunimitsu Honda prepared and entered a naturally aspirated Acura NSX into the GT2 class numbered 84; a fourth GT2 NSX was entered by Nakajima Racing with number 85 but failed to pre-qualify. Car 46 finished but was not classified for failing to complete 70% of the distance of the race winner. Car 47 did not finish due to clutch and gearbox failure. Car 84, driven by Keiichi Tsuchiya, Akira Iida, and Kunimitsu Takahashi, finished 8th overall winning the GT2 class after completing 275 laps. This Acura NSX was featured in the original Gran Turismo, with the GT1 class car being featured in the Japanese version of the game instead.
For the 1996 24 Hours of Le Mans, only the Team Kunimitsu Honda NSX returned with the same drivers. It completed 305 laps to finish in the 16th position overall, and third in the GT2 class.
1995 Class Winning Acura NSX-GT2 Le-Mans Racer
For use in the Super GT (formerly the JGTC), the Acura NSX has been highly modified (as allowed by series technical regulations) with chassis development done by Dome, engine development by Mugen, for Honda. Prior to the official debut in 1997, Team Kunimitsu entered the first Acura NSX in the series, similar to the 1995 Le Mans GT2 car in specification, in the 1996 season.
Externally, the Acura NSX’s shape has developed race by race, season to season to the demands of increasing aerodynamic downforce within the regulations. The most notable change is the position of the V6 engine, which is mounted longitudinally instead of transversely as per the road car. Similar to the setup used in modern Lamborghinis, the gearbox is located in the center tunnel under the cockpit and is connected to the rear differential by a driveshaft. Engines can either be turbocharged or naturally aspirated, depending on the class and on the rules.
Prior to rule changes beginning in the 2003 season, the Super GT/GT500 NSX was powered by a specially modified version of the C32B V6 engine. Using a stroker crankshaft from Toda Racing, the naturally aspirated engine displaced 3.5-litres and produced nearly 500 hp (373 kW; 507 PS). Beginning in 2004, Honda Motor Company substituted a highly modified C30A engine, augmented by a turbocharger, which also produces up to 500 bhp, but the following season reverted to naturally aspirated C32B due to cooling problems.
The Acura NSX continued to be used as the works Honda car in the GT500 class, even though it is no longer in production, until it was replaced in 2010 with the HSV-010. New 2014 regulations however will render the HSV-010 obsolete; Honda’s 2014-spec GT500 car is to be based on the concept version of the new NSX, followed with a Group GT3 version from 2017 onwards.
The Acura NSX-GT was used in the series between 1997–2009, and it was one of the most successful cars to race in the series. It won 36 races, 45 pole positions, three teams’ and two drivers’ championships and finished runner-up in the drivers’ championship six times when it didn’t win it. It also won the Suzuka 1000km four times; in 1999, 2000, 2003 and 2004. It is the only Japanese car in the series to score pole position and fastest lap in every race of the season, holds the record for the most consecutive wins at six and is the first car to win the championship prior to the final race. A GT300 specification Acura NSX won the GT300 class titles in 2004.
2000 Acura NSX-GT500 Honda Collection Hall
Honda NSX Super GT specifications
Year 2009 final specification
- Chassis: Carbon fiber reinforced aluminium frame, steel Roll cage, JAF (Japan Automobile Federation) approval.
- Engine: Custom-built Hondaengine, water-cooled V6 Normally aspirated (Longitudial-mounted), 3.494 liters, DOHC, 4-valves per cylinder.
- Speed: 191 mph (307 km/h)
- Fuel: Unleaded 100 RON
- Lubrication: Mobil 1, Castrol, MOTUL, Elf.
- Fuel delivery: Fuel injection.
- Wheelbase: 2,530 mm.
2001 Acura NSX-GT
The Acura NSX was entered in the SCCA World Challenge prior to the redesign in 2002. It won the championship in 1997, driven by Peter Cunningham.
Since the beginning of the Acura NSX‘s production, the car has been used as a safety car at the Suzuka Circuit, even for the Japanese Grand Prix in its early years of production, and is still used at the circuit. The car is also used for the same role at Twin Ring Motegi, the other circuit owned by Honda.