NSU Ro 80
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|NSU Ro 80|
|Production||1967-1977 with 37,204 examples|
|Body Style||Four-door saloon sedan|
|Power||115 hp @ 5500 rpm|
|Similar||Citroen GS Birotor|
The NSU Ro80 was produced by German company NSU between 1967 and 1977. The Ro80 was a very advanced automobile, becoming the first production car to feature the Wankel Rotory engine. NSU had never created such an expensive or large car before, and to design the flagship, stylist Claus Luthe was employed - the shape created was particularly aerodynamic, and the sales material for the Ro80 traded heavily upon this factor, despite the aerodynamics being developed soley by Luthe's guesswork until true development of the car was under way.
The car was sold only with the rotor engine option, which had a lack of mid-range torque and power - to hide this shortfall, a three-speed semi-automatic transmission was applied to the car. Unfortunately, the twin-rotor engine was unreliable in its earlier states, due to the wearing of the rotor tip seals. The fault, attributed to under-development, hindered the Ro80 with an unshakeable reputation for unreliability - but NSU was generous with warranty claims, and some cars have had as many as nine new engines.
Ultimately, the warranty liberty given by NSU led to its downfall - the company, teetering on the edge of financial meltdown, was acquired by Volkswagen in 1969.
See Wikicars' comprehensive NSU Ro80 Review.
The Ro80 had many other mould-breaking features other than the twin-rotor engine. The engine itself was of 995 cc capacity, and produced 115bhp - enough to power the Ro80 to a top speed of around 115mph.
Firstly, the vehicle featured four full-size disc brakes, which had rarely been seen on anything other than supercars on release in 1967, due to the expense required. The Ro80's engineers worked hard both on the brakes themselves, which were noted by period motoring press to be 'superior', but also the packaging - the front brakes were mounted inboard, which meant less weight was carried by the suspension, reducing unsprung weight.
Independent suspension was used on all four wheels, with straight-forward MacPherson struts at the front but a trailing-arm set-up at the rear. To guide the front wheels, NSU employed one of the world's first power steering systems - a powered rack and pinion set-up.
The Sachs/NSU collaboration developed semi-automatic transmission was also a new feature, foreshadowing modern sports car transmissions such as Porsche's Tiptronic or Lamborghini's e-Gear. However, instead of a clutch pedal for the manual shifts, a switch incorporated into the gear knob activated a pneumatically operated clutch lever via a solenoid valve unit, which would let the clutch in slowly at idle engine speeds or when the throttle was closed (e.g changing down), or quickly during acceleration to achieve fast drive take up between gears when changing up. The clutch itself, a conventional friction lined device, sat between a conventional 'auto-box' Sachs torque converter and the three speed manual transmission, so that the engine could idle (torque converter stalled) with a gear selected at standstill. This provided the usual idle creep mode that so aids slow speed manouvering (parking).
Styles and Major Options
The Ro80 was only supplied in four-door sedan format, but the styling was oft talked about. With a coefficient of drag of only 0.355, the Ro80 was miles ahead of its competition, and even some modern cars struggle to match this figure. Although NSU claimed that the car had been developed extensively in a wind-tunnel, the Luthe design had only seen the inside of the Stuttgart Technical Research Centre's wind tunnel in the twilight stages of its development - Luthe managed to create the aerodynamic form soley by using his eye and educated guesswork.
The Ro80 is celebrated amongst the car design world as the shape which most designers would like to see in their own portfolio - a sentiment most notably echoed by Bruno Sacco of Mercedes-Benz. The form has dated very well, and it is only the chrome brightwork, light units and narrow, tall tyres which indicate the era of the car.
Throughout its ten-year lifespan, the Ro80 was rarely changed stylistically. Minor ancillaries, such as door mirror design and wheel shape (culminating in Fuchs forged wheels, similar to that of the Porsche 911) were modified. The most major change for the 1973 model year was within the interior, where higher backed front seats with head restraints were introduced to improve comfort and passenger safety. This move also brought the dropping of the 60's style leatherette seat material, with velour becoming a more luxury fitting. Genuine leather seat coverings were an option, though rarely chosen. The very last cars were fitted with modified (larger) tail lights, with a brushed aluminium blanking section covering the rear panel where the boot (trunk) lock used to be, the trunk lock itself being moved to the boot lid, where the Audi 100 lock was substituted in. Colour options were also rather stagnant, with each model year yielding only the addition or subtraction of the odd colour, as opposed to the complete colour option reshuffles which take place nowadays. The colours themselves, and the interior colours, were very typical of the period.
The Ro80, sold by NSU alongside Volkswagens and Audis, retailed for around $5,000 in 1967. Prices remained similar throughout its life.
The Ro80 was deemed reasonably economical, returning around 25 miles-per-gallon (mpg) on a higher speed (70 mph) run, but this could drop to 15 mpg or less around town. The operation of the Wankel being akin to a two stroke requires that oil (in this case the actual engine oil) is mixed with the incoming fuel at the engine mounted petrol pump to lubricate the combustion chambers seals, with the result that owners reported that the twin-rotor engine used a lot of oil, more so than contemporary Audi and Volkswagen sedans. Signs afixed to the front windscreen told owners to check the oil each time the car was filled up with fuel.
The early Wankel rotory engines utilised by NSU were woefully unreliable. A poor mechanical knowledge of the new-fangled engine, along with a rushed development, meant that a flawed engine was fitted to the first batches of Ro80s - and reports started to circulate about owners noticing a loss in power and torque of their engines, along with increased fuel consumption and masses of smoke coming from the car. The problem was traced to acute wear of the rotor tip seals. The problem occurred as early as 15,000 miles, but NSU was very generous with warranty claims, granting a new engine to every owner with a worn-out one. Some cars had numerous new engines. However, NSU began to redevelop the engine, and later cars featured more reliable powerplants. But it was not enough, and the car had been fostered with a reputation for unreliability. Sales collapsed, and a desparate NSU hatched plans to scrap the rotor engine completely and launch a traditional internal combustion example - this was approved but never developed.
The numerous warranty claims made by NSU cost the company dearly - and by 1969, it was on its last legs, financially. It was bailed out by VW in 1969, who continued to fund Ro80 warranty claims for the remainder of its life.
Some cars have had their engines after-market replaced with traditional engines from other manufacturers - these should be crtically scrutinised by proposed purchasers as the quality of the conversion is paramount to the cars long term future. Early solutions to the engine conversion question used the Ford narrow angle 2000 CC V4 engine from the Corsair. This conversion is to be avoided due to the general poor quality of some conversions and the lack of adequate match of the cars gear ratios to the V4 engine performance. Later conversions to the Mazda Rx7 12A and 13B engines were available with professionally produced conversion parts. Though not for the purist, these conversions provide a virtually bomb proof Wankel replacement for the NSU powerplant, giving everyday reliability to an otherwise highly competent car. The major difference to tha car when fitted with the Mazda Wankel is the harsher tone of the Mazda unit, and the significantly increased torque at lower RPMs, due to the effective inlet timing difference, provided by the side ported Mazda inlet tracts, as opposed to the periferally ported inlet NSU system.
Due to the solid and thorough design of the chassis and structure, the Ro80 was solid in a crash. Compared with its contemporary brethren, it excelled, although it cannot be compared to modern standards of crash protection. Even so, it was built with large tripple section box sills to strengthen the side of the car and move the passengers towards the centre of the vehicle. It was also constructed with padded internal surfaces to help prevent passenger injury. It was one of the very first vehicles to also offer front and rear crumple zone protection to the passengers. Front seat belts, were fitted as standard to the car, and rear seat belt anchors were available, though early cars could only be fitted with static rear belts.
Each NSU Ro80 has the colour option code listed on the Vehicle Identification Panel. The colours are as follows:
R3 - Alaska White
D3 - Sahara Beige
G7 - Coral (Red)
G3 - Iberian Red
J4 - Smoke Blue
K1 - Deift Blue
T1 - Agate Brown
N6 - Tropic Green
T4 - Maroon
B7 - Corona Yellow
N1 - Bermuda Green
E4 - Tibet Orange
A1 - Black
X2 - Metallic Marathon (Silver)
X4 - Metallic Blue
Y4 - Light Metallic Turquoise
Z3 - Metallic Colorado (Red)
Z1 - Metallic Agate (Brown)