Hubbry Logo
NSU SpiderNSU SpiderMain
Open search
NSU Spider
Community hub
NSU Spider
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
NSU Spider
NSU Spider
NSU Spider
View on Wikipedia
from Wikipedia
NSU Spider
Overview
ManufacturerNSU Motorenwerke AG
Production1963–1967
2,375 built
AssemblyWest Germany: Neckarsulm
DesignerBertone
Body and chassis
Body style2-door cabriolet
LayoutRR layout
Powertrain
Engine1.0 L KKM 502 (Wankel)
Transmission4-speed all-synchromesh manual
Dimensions
Wheelbase2,020 mm (79.5 in)
Length3,580 mm (140.9 in)
Width1,520 mm (59.8 in)
Height1,260 mm (49.6 in)
Curb weight700 kg (1,500 lb)
(Measurements approximate)
The engine bay had originally been designed to take the four-stroke air-cooled two-cylinder engine from the NSU Prinz. The rotary unit was much more compact permitting a shallow luggage locker fitted above it. This compensated for a reduction in luggage space at the front of the car because of the front mounting of the cooling radiator.

The NSU Spider is an automobile which was produced by NSU Motorenwerke AG from 1963 to 1967.[1]

The Spider was the first Western production car in the world to be powered by a Wankel rotary engine.[2] The water-cooled single rotor engine and standard front disc brakes differentiated the car from other cars of similar type of the period. The body was designed by Bertone.[3]

Body

[edit]
NSU Spider (rear view)

First appearing in 1963,[4] the Spider featured a two-door cabriolet body based on that of the NSU Sport Prinz coupé introduced in 1959. In addition to the folding roof, the Spider was distinguishable from the hard top car by a grill at the front. As with all NSU cars at the time, the engine was rear-mounted: in order to improve weight distribution, space was found for the Spider’s radiator and for its 35-litre (9 US gal; 8 imp gal) fuel tank ahead of the driver. The front luggage locker was, in consequence, small. There was a second luggage area in the rear of the car above the engine.

Rotary engine

[edit]

The NSU Spider is the first series production car powered by a Wankel rotary engine. In the Spider, a KKM 502 single-rotor engine with a single spark plug was used; it has a chamber volume of 498 cc (30 cu in), and displaces 996 cc (61 cu in) from a generating radius of 100 mm, a width of 67 mm, an eccentricity of 14 mm and an equidistant of 2 mm. Compression is 8.5, and the fuel required is petrol with an octane rating of 91 RON. The Spider's engine had "teething troubles", but is a compact, smoothly running engine with a decent power output. Rated power was initially 50 PS (37 kW) at 5,500 rpm. In later models, rated power was 54 PS (40 kW) at 6,000 rpm.[citation needed] Maximum torque output is 79 N⋅m (58 lb⋅ft) at 3,500 rpm,[citation needed] equivalent to a BMEP of 1 MPa (145 lbf/in2).[4] It was later found that the characteristics of critical materials selected and applied by NSU to build production rotary engines were inappropriate to the stresses they would bear, and rotary-engined cars earned a reputation for unreliability. Engines required frequent rebuilding to replace worn apex seals, and warranty costs associated with installation of the engine in NSU’s second Wankel-engined model destroyed the financial viability of NSU, forcing a merger with Audi in 1969.[5] The rotary engine was installed above the rear axle, being compact, light and free revving in comparison with conventional piston engines of the time. By ignoring the manufacturer's recommendations it was possible to rev the engine briefly above 7,000 rpm in the lower gears and thereby to achieve a 0 – 100 km/h (0 – 62 mph) time of 14.5 seconds: other sources, presumably based on following the manufacturer's recommendations, give a time of 15.7 seconds.

Commercial

[edit]

Large sales volumes were never envisaged for the car, and this was reflected in a relatively high retail price, USD$2,979.[5] Between 1964 and 1967 2,375 were built. In 1967, the model was withdrawn and NSU's second rotary-engined production saloon was presented. The Ro 80, totaled 37,398 units during its ten year production run.

In 1966, Al Auger of Richmond, California, became the first person to race a Wankel-powered production car in an officially sanctioned race. After only installing a mandatory roll-bar and racing tires on an NSU Spider, Auger raced in 1966 and 1967 in Sports Car Club of America sanctioned road races throughout California finishing second overall in the championship both years in Class H Modified. Because SCCA had no technical information about the Wankel engine it was placed in H Modified racing against lighter, more powerful, 850 cc highly modified pure racing cars.

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

NSU Spider

View on Grokipedia
from Grokipedia
The NSU Spider, formally known as the NSU Wankel Spider, is a two-seat open-top roadster produced by the German automaker AG from late to July 1967. It holds historical significance as the world's first series-production automobile powered by a Wankel , specifically a water-cooled single-rotor KKM 502 unit with 498 cc displacement that initially delivered 50 PS (37 kW) at 5,500 rpm and 71 Nm of torque at 2,500 rpm, later increased to 54 PS (40 kW) at 6,000 rpm. Featuring , a four-speed , and a lightweight styled by Bertone, the car achieved a top speed of approximately 153–158 km/h (95–98 mph) and accelerated from 0–100 km/h in about 14 seconds, despite its modest power output. Development of the Spider stemmed from NSU's pioneering collaboration with inventor in the , evolving from early rotary tested in NSU's Prinz models to this dedicated unveiled as a fully drivable at the 1963 Frankfurt International Motor Show. The engine, weighing just 125 kg including auxiliaries, was mounted low behind the passengers for balanced handling, contributing to the car's smooth, low-vibration operation that was quieter than contemporary engines. Offered in colors like Alfa Red or Lily White at a launch price of around 8,500 Deutsche Marks (equivalent to about $2,125 USD at the time), it targeted enthusiasts with its innovative technology and sporty aesthetics, though early Wankel issues such as apex seal wear and high fuel consumption limited its commercial success. Only 2,375 examples were manufactured at NSU's facility, making the Spider a rare collector's item today and a crucial stepping stone for adoption. Its introduction sparked widespread interest, leading to licensing agreements with companies like , , and , and directly influenced NSU's subsequent twin-rotor Ro 80 sedan launched in 1967. Despite NSU's eventual acquisition by Volkswagen-Audi in 1969 and the phasing out of rotary production due to reliability challenges, the Spider remains celebrated for pioneering compact, high-revving rotary power in a production vehicle.

Development

Conception

In the early 1960s, , a German manufacturer with a long history in motorcycles and automobiles, intensified its collaboration with inventor , which had begun in the 1950s, to refine and productionize the rotary piston engine concept. Under chief engineer Walter Froede, NSU's engineers addressed initial challenges like sealing and complexity by transitioning from Wankel's early DKM designs to the more practical KKM series, testing prototypes in existing models such as the and Sport Prinz by 1959. This experimentation positioned NSU as a pioneer in rotary technology amid a European automotive landscape seeking innovative powertrains to compete with established piston engines. By 1963, NSU decided to create a dedicated lightweight to demonstrate the rotary engine's potential, drawing inspiration from the rear-engine NSU Sport Prinz coupé introduced in 1959. The choice of a halo vehicle aimed to maximize exposure for the compact, high-revving rotary, which promised superior power-to-weight ratios compared to conventional engines. Unveiled as the NSU Wankel Spider at the International Motor Show that year, the project emphasized a cabriolet body style to distinguish it from NSU's lineup of sedans and coupes, evoking the open-top allure of European sports cars like the MG or . NSU partnered with Carrozzeria Bertone for the styling, under the direction of "Nuccio" Bertone, to craft an eye-catching design that complemented the engine's attributes. Key goals included achieving a curb weight under 700 kg to enhance agility and performance, targeting around 50 horsepower from the single-rotor unit for a top speed exceeding 150 km/h, while appealing to enthusiasts seeking a vibrant, low-vibration driving experience. This conception marked NSU's bold entry into the sports car segment, leveraging the rotary's smoothness and compactness to challenge traditional notions of automotive propulsion.

Prototyping and Testing

The development of the NSU Spider involved constructing prototypes based on a modified chassis from the NSU Sport Prinz, adapting it to accommodate the innovative single-rotor Wankel engine as a showcase for rotary technology. The first prototype was completed in time for the vehicle's public debut at the 1963 International Motor Show in Frankfurt, where it was presented as a fully drivable open-top two-seater designed by Bertone. Testing commenced shortly after the 1963 unveiling, with initial road trials conducted at NSU's facilities in to evaluate overall reliability and integration of the rear-mounted water-cooled Wankel engine, which required a front-positioned for cooling. Key challenges included the engine's , as the rotary unit was housed in the rear luggage compartment under a separate cover, necessitating complex ducting for flow from the front to maintain management without compromising . Additionally, the rear-wheel-drive layout posed handling concerns due to the engine's positioning, prompting evaluations of stability during cornering. A primary focus of the testing phases was the durability of the Wankel engine's apex seals, which were critical for maintaining compression but prone to wear under prolonged road conditions, leading to issues like gas leakage and reduced efficiency. Road trials emphasized long-term reliability, with prototypes undergoing extensive mileage accumulation to assess seal , ultimately incorporating refinements such as metal-impregnated apex seals and chromed housings to target a 50,000-mile before production. Suspension tuning, utilizing independent double wishbone at the front and semi-trailing arms at the rear, was adjusted during these tests to improve handling poise and reduce oversteer tendencies inherent to the rear-engine configuration. The folding cabriolet roof mechanism also received attention, with iterations to simplify operation, though early versions required two-person effort for deployment.

Design

Body and Chassis

The NSU Spider featured a rear-engine, (RR) layout in a compact 2-door cabriolet body style, which contributed to its agile handling and balanced weight distribution. This configuration placed the engine at the rear, optimizing space for a design. Key dimensions included a of 2,020 mm, overall length of 3,580 mm, width of 1,520 mm, height of 1,260 mm, and a curb weight of approximately 700 kg, making it one of the lightest production s of its era. The body utilized a unibody construction derived from the NSU Sport Prinz coupé, providing structural rigidity while keeping weight low for enhanced performance. A manual folding soft-top roof allowed for open-air driving, with the mechanism designed to fold neatly behind the seats when not in use. Exterior styling, penned by Italian design house Bertone, emphasized aerodynamic efficiency with sleek, flowing lines suited to its open-top profile. Notable features included a distinctive front grille that set the Spider apart from its counterpart, along with dual luggage compartments—one in the front sharing space with the and , and a smaller one behind the seats for added practicality. These elements combined to create a visually striking and functional lightweight roadster.

Interior and Features

The NSU Spider was designed as a compact two-seater roadster, featuring bucket seats that provided ample padding for driver and passenger comfort in line with mid-1960s German standards. The seating layout prioritized a driver-focused experience, with the compact cabin layout allowing for straightforward entry and a low-slung driving position that enhanced the feel. Upholstery options included vinyl, , or cloth, often in two-tone configurations that extended to the simple panels for a cohesive, minimalist aesthetic. The was compact and ergonomically arranged to emphasize the driver, housing essential analog instrumentation such as a integrated with a trip meter and , a , and a . Controls were straightforward and manual, including a steering system without power assist, ignition and starter switch, fresh air vent, temperature control, heater fan, headlight switch, windshield wiper and washer, ashtray, and cigarette lighter. Standard amenities encompassed a heater and demister for basic climate control, while a radio was not included as standard equipment. Additional features like a glove box and grab handle contributed to the spartan yet functional interior. A key unique element was the integrated storage for the folding convertible top, accommodated by dedicated provisions in the body design to maintain cabin usability. For safety and comfort, the car included a steering lock and basic lap seatbelts, which became more standard in later production years amid evolving regulations; however, sound insulation was minimal, allowing the distinctive whir to permeate the cabin.

Engine and Drivetrain

Wankel Rotary Engine

The NSU Spider was powered by a single-rotor KKM 502 Wankel rotary engine, featuring a displacement of 498 cc. This compact unit utilized an eccentric shaft to drive the triangular rotor within an epitrochoidal housing, enabling a smooth, vibration-free rotation that completed intake, compression, combustion, and exhaust in a single rotor revolution. Apex seals at the rotor's vertices maintained compression by sealing against the housing walls, while the engine required 91 RON petrol to accommodate its 8.5:1 compression ratio and prevent knocking. Initial production models delivered 50 PS (37 kW) at 6,000 rpm, with later versions upgraded to 54 PS (40 kW) at 6,000 rpm through refinements in carburetion and sealing. The engine's design incorporated metal-impregnated rotor tip seals and a chromed inner housing surface to enhance durability, lubricated via a with a full-flow filter and cooler. Weighing approximately 125 kg including the , starter, and transmission, it was rear-mounted above the axle for optimal , paired with a front-mounted and ducted airflow for efficient cooling of the inherently hot-running rotary. As the first Western production car to employ a , the KKM 502 represented a pioneering shift from traditional designs, offering low noise and exceptional smoothness akin to a six-cylinder inline engine despite its single . This innovation allowed for a space-efficient layout, freeing up cabin room and enabling dual trunks, while the rotary's high-revving nature provided responsive power delivery. Despite its advancements, the KKM 502 suffered from notable reliability issues, primarily rapid wear of the soft carbon apex seals, which often limited engine life to around 50,000 miles and necessitated frequent replacements. High oil consumption was inherent to the design, as premixed oil was required to lubricate the seals and housing, contributing to elevated maintenance demands and operational costs. These "teething troubles," including poor shaft lubrication and seal failures, underscored the challenges of early rotary technology and led to significant claims for NSU owners.

Transmission and Performance

The NSU Spider utilized a four-speed with all-synchro gears, driving the rear wheels in a rear-engine, rear-wheel-drive configuration. An optional was available to improve traction on slippery surfaces. This setup provided straightforward shifting and adequate gear ratios for the car's modest power output, with first gear allowing acceleration up to approximately 47 km/h and top gear enabling cruising speeds around 150 km/h. Performance metrics reflected the single-rotor Wankel engine's characteristics, delivering 71 N⋅m of at 3,500 rpm to achieve 0–100 km/h in about 14.5 seconds and a top speed of approximately 154 km/h. The lightweight construction, at around 700 kg, contributed to responsive dynamics, though the rotary's high-revving nature required rev-matching for optimal shifts. Fuel efficiency averaged 10–12 L/100 km in mixed driving, higher than comparable piston-engined sports cars due to the Wankel design's inherent thirst. Handling benefited from the car's low center of gravity and agile proportions, with independent front suspension using unequal-length A-arms, coil springs, and an anti-roll bar for precise steering via rack-and-pinion. The rear suspension employed semi-trailing arms with coil springs, promoting stability, but the rear-engine placement led to oversteer tendencies under hard cornering, demanding careful throttle control. Overall, these traits made the Spider nimble for twisty roads, though its performance prioritized smoothness over outright speed.

Production and Sales

Manufacturing Details

The production of the NSU Spider commenced in the fall of 1964 at NSU's facility in , , and concluded in July 1967, resulting in a total of 2,375 units manufactured. Assembly occurred exclusively at the plant, where the Bertone-designed steel body was welded and fitted with components, including the installation of the single-rotor beneath the rear floor. Given the limited production run, the process emphasized manual craftsmanship in integrating the innovative rotary powertrain, with particular attention to for engine seals and overall fitment. In 1966, minor updates were introduced, including an increase in engine output from 50 horsepower to 54 horsepower, enhancing performance while maintaining the core design.

Market Reception and Pricing

The NSU Spider was unveiled at the 1963 International Auto Show as the world's first series-production car to be powered by a Wankel (although production began in late 1964), where it garnered significant attention marking a bold step in automotive innovation. NSU marketed the Spider emphasizing its smooth engine character and compact performance, targeting buyers seeking a fresh alternative to traditional piston-engined roadsters in the European market. At launch, the base price was set at approximately 8,500 German Marks in , with a U.S. market price of about $2,998, making it competitively priced against entry-level sports cars like the while highlighting the rotary engine's exclusivity. This pricing strategy aimed to attract budget-conscious drivers interested in advanced without the premium of larger luxury convertibles. Sales focused mainly on European markets, with only limited exports to the U.S., with approximately 215 units sold in the U.S., where dealer networks struggled with parts availability and support. Overall performance was subdued due to escalating claims from persistent issues, particularly apex seal wear that led to frequent failures and repairs. The Spider received praise from automotive press for its revolutionary powertrain and engaging driving dynamics, often noted for the rotary's distinctive whine and vibration-free operation. However, critics and owners frequently highlighted reliability shortcomings, with engine durability problems overshadowing its innovations and deterring repeat buyers. In comparison to contemporaries like the Spider—a more affordable option at around $2,000 with a conventional inline-four —the NSU was lauded for uniqueness but faulted for higher operating costs and less dependable long-term ownership.

Legacy

Impact on NSU

The NSU Spider's introduction of the in a brought significant financial strain to NSU, as frequent failures, especially apex seal wear, led to substantial claims and replacement costs that eroded the company's reserves. By the mid-1960s, these issues, compounded by similar problems in other rotary-powered models like the , pushed NSU toward bankruptcy risks, with repairs alone costing millions and contributing to mounting debt. This financial pressure culminated in NSU's acquisition by in 1969, followed by its merger with to form Audi NSU Auto Union AG in 1969, effectively ending NSU's independence as a standalone automaker. Technologically, the Spider served as a critical testbed for the , directly paving the way for NSU's more refined application in the Ro 80 sedan, which entered production in 1967 and featured an improved twin-rotor design. The Ro 80, produced until 1977 with a total of 37,398 units, represented NSU's pinnacle of rotary innovation, earning acclaim for its advanced engineering despite inheriting some of the Spider's foundational limitations. However, the persistent reliability challenges highlighted by the Spider underscored the rotary engine's practical shortcomings, such as high fuel consumption and maintenance demands, which tempered its long-term viability within NSU's lineup. The Spider's legacy influenced the broader by demonstrating the rotary engine's potential for compact, high-revving power in a lightweight chassis, inspiring interest from manufacturers like . Yet, its pronounced reliability issues, including excessive wear and emissions difficulties, reinforced skepticism about the technology's scalability, ultimately influencing Audi's decision to abandon further rotary development after the Ro 80's production ended in 1977, shifting focus to conventional piston engines amid rising fuel costs and regulatory pressures.

Collectibility and Racing History

The NSU Spider's limited production run of 2,375 units from 1964 to 1967 has established it as a rare collectible among enthusiasts of vehicles. This scarcity, combined with its historical significance as the first production car powered by a Wankel , drives demand in the market. Well-preserved examples in good condition typically command values around $20,500, while exceptional sales have reached up to $35,000, as seen in auctions through 2025. Restoration efforts are complicated by the scarcity of rotary-specific components, such as apex seals and housings, which often require custom fabrication or sourcing from specialist suppliers due to the engine's limited production lifespan. In its era, the NSU Spider saw limited but notable involvement in , primarily in the United States. Between 1966 and 1967, examples were entered in (SCCA) road races in , marking the debut of Wankel-powered production cars in officially sanctioned competition. Driver Al Auger of , achieved second place overall in Class H Modified during both years, competing against lighter vehicles with engines up to 850 cc despite the Spider's relative underdevelopment. These entries often featured modifications like tuned rotary engines for improved power output and reliability, though the class placement stemmed from a lack of official technical data on the Wankel design at the time. Today, the NSU Spider garners sustained interest from collectors and historians, frequently appearing in prominent car shows and museums that highlight innovative engineering. Examples have been displayed at events like the Greenwich Concours d'Elegance and the Klassikwelt Bodensee, where their Bertone styling and rotary heritage draw admiration. Institutions such as the Lane Motor Museum in Nashville, the Collection in the UK, and the NSU Classic Museum in , , house preserved specimens, underscoring the model's role in automotive innovation. Preservation is supported through Audi's heritage initiatives, which maintain access to original NSU parts and technical for restoration projects. The program, commemorating NSU's legacy since the merger, facilitates sourcing of components like seals and body panels via specialized suppliers, helping owners overcome the challenges of the rotary powertrain's apex wear and oil consumption issues. Enthusiast networks further aid maintenance by sharing expertise on reliable aftermarket adaptations, ensuring the Spider's drivability for modern use.

References

  1. https://www.audi-mediacenter.com/en/press-releases/sporty-beautiful-and-innovative-the-nsuwankel-spider-15608
  2. https://www.hemmings.com/stories/whirl-premiere-1967-nsu-spider/
  3. https://www.automobile-catalog.com/make/nsu/spider_nsu/spider_nsu/1964.html
  4. https://ateupwithmotor.com/model-histories/nsu-ro80-history/3/
  5. https://www.uniquecarsandparts.com/nsu_spider_technical_specifications.htm
  6. https://www.lanemotormuseum.org/collection/cars/item/nsu-wankel-spider-1967/
  7. https://www.hemmings.com/stories/cars-of-futures-past-1964-1967-nsu-spider/
  8. http://cp_www.tripod.com/rotary/pg05.htm
  9. https://ateupwithmotor.com/model-histories/nsu-ro80-history/
  10. https://www.autocar.co.uk/car-news/1965-nsu-wankel-spider-road-test-throwback-thursday
  11. https://www.carfolio.com/nsu-wankel-spider-69509
  12. https://www.automobile-catalog.com/car/1965/2057690/nsu_spider.html
  13. https://www.hotcars.com/nsu-wankel-spider-a-forgotten-sports-car-that-rebelled/
  14. https://www.autoweek.com/car-life/a1947051/classic-drive-1966-nsu-spider/
  15. https://bringatrailer.com/listing/1967-nsu-wankel-spider-3/
  16. https://www.pressreader.com/usa/old-cars/20230215/281827172877874
  17. https://wiki.cdd.no/index.php/Wankel_engine
  18. https://www.hemmings.com/stories/1965-67-nsu-spider/
  19. https://ateupwithmotor.com/model-histories/nsu-ro80-history/4/
  20. https://www.classic-trader.com/au/cars/listing/nsu/wankel-spider/wankel-spider/1966/392883
  21. https://www.classic.com/m/nsu/spider/
  22. https://fastestlaps.com/models/nsu-spider
  23. https://classicmotorsports.com/articles/we-had-mazda-rx-7-nsu-gave-us-their-rotary-powered/
  24. https://www.jdpower.com/cars/1964/nsu/wankel-spider/2-door-convertible
  25. https://www.hotcars.com/nsu-wankel-spider-costs-facts-and-figures/
  26. https://www.sportscarmarket.com/profile/choose-wisely-or-not-at-all
  27. https://www.autoweek.com/news/a2068406/1967-nsu-wankel-spider-rev-it/
  28. https://www.retromotor.co.uk/great-motoring-disasters/nsu-ro80/
  29. https://www.curbsideclassic.com/automotive-histories/automotive-history-german-deadly-sins-the-neckarsulm-chronicles-part-3-the-nsu-ro-80-todsunde-durch-technik/
  30. https://www.drive.com.au/caradvice/1968s-car-of-the-year-was-a-revolution-and-a-gloriously-noble-failure/
  31. https://www.evo.co.uk/features/16751/rotary-engined-cars-past-present-and-future
  32. https://www.nytimes.com/2008/11/02/automobiles/collectibles/02ROTARY.html
  33. https://www.hagerty.com/valuation-tools/nsu/wankel_spider/1967/1967-nsu-wankel_spider
  34. https://barnfinds.com/rotary-racer-1966-nsu-spider/
  35. https://www.uniquecarsandparts.com/car_info_nsu_spider.htm
  36. https://greenwichconcours.com/files/event_program/1718023196.3331_nj6gn964.pdf
  37. https://www.youtube.com/watch?v=haGHHiVjoo
  38. https://collection.sciencemuseumgroup.org.uk/objects/co25294/n-s-u-spider-motor-car
  39. https://audi-tradition-parts.de/en_GB
Add your contribution
Related Hubs
User Avatar
No comments yet.