The NSU Ro80
A Very Advanced Wankel-Rotary-Engined Front-Drive Saloon from Neckarsulm Which Provides Superb Road-Holding, Comfort, Speed and Safety.
There have not been many truly revolutionary cars in all the long history of motoring. Back in 1902 Mercedes introduced that much-quoted 40-h.p. model which incorporated many up-to-date features from other makes, such as a steel channel-section frame, honeycomb radiator, gate gear-change and a variable rather than a fixed-speed engine, which, depending on how you look at it, set a fashion in sophisticated design or retarded ingenious development, almost to the present day. Dr. Lanchester had designed and constructed far more scientific and satisfactory motor-carriages much earlier, so that, there being no way of improving on them, the Lanchester can be said to have deteriorated with the passage of time.
Along the years there have been numerous instances of technical advancement in one single aspect of the motor car—front-wheel-drive, independent front suspension, elimination of leaf springs, foolproof transmissions, streamlined rear-engined pear-drops from the Rumpler onwards, the current mid-engine conception and so on—but very few entirely revolutionary projects, in the commercial field. Citroën took a courageous stride forward with the DS but came to this via the pre-war Citroën’s which had traction avant, torsion-bar suspension and “a wheel at each corner” to distinguish them from the dull though useful Citroëns of the ‘twenties and early ‘thirties. The DS merely improved on this excellent theme of comfort and superior road-holding.
Rolls-Royce supremacy was based on the triumph of conscientious construction over sober design, up to the Clouds. It is only in the Silver Shadow that Britain’s best car has taken on the mantle of the revolutionary.
With NSU it has been similar. They began as makers of bicycles, motorcycles, and then nicely-finished small cars of “cyclecar” type, until someone at Neckarsulm sanctioned the taking of a clean sheet of drawing paper for the execution of a very sophisticated and revolutionary (in more senses that formerly implied) medium-sized luxury family car.
It began when the German Company (which takes its initials from the “N” and the “SU” of the town where it is situated) tested a rotary engine early in 1957. By 1964, when NSU were making more than 200,000 cars a year, including an o.h.c. air-cooled four-cylinder, a single-unit Wankel rotary power unit had been approved for the rear-engined NSU Spyder. This was the outcome of road-testing a rotary engine in a Spyder over the previous four years, and experiments with boat and fire-pump versions. At this time Motor Sport went to Neckarsulm to study the prospects (we also visited the NSU Museum) but at this stage the Press was not permitted to drive the Wankel cars. What we saw impressed us, however, and it seemed certain that NSU would soon produce a rotary-engined car for the buying public.
Since then I have had the experience of the single-rotor Wankel engine in an NSU Spyder and the twin-Wankel in that very fine sports car, the Mazda 110S. From comparatively inexpensive air-cooled small cars with the sting in their tails to a twin-Wankel water-cooled front-drive saloon with chassis and body-form sophistication in keeping with its revolutionary engine was a formidable step. The first aerodynamic tests on the Ro80 were done at Stuttgart Polytechnic on a model nearly six years ago. At the 1935 Frankfurt Show NSU exhibited a 2 x 500-c.c. 110-b.h.p. twin-rotor engine. This engine was ready for the Press to sample in a truck in 1966 and meanwhile a full-size car had been aerodynamically tested. At the factory this was known as the Type 80 and secret road tests commenced in the summer of 1966. That autumn the Wankel pattern was given an impetus when Panowitz/Stunz won the German GT Rally Championship with an NSU Wankel Spyder. A year later, at the 1967 Frankfurt Show, the production version of the Ro80 was revealed to the public, a car its makers think may have a little competition by 1978! Production of this advanced and well-received motor car began in mid-October of that year and it was proclaimed the “Car of the Year.”
We could have flown to Germany to try this new model but we preferred to wait for the initial fever to die down and the model to get into steady production before sitting in judgement on, or in, it. Fashions change fast in the world of motoring and the Jaguar XJ6 has since been proclaimed superior to the Wankel-NSU by those who look after this “Car of the Year” thing, in spite of the its out-dated “interim” means of propulsion.
So I am writing now about a widely and wildly proclaimed car which has been out and about and freely-discussed for more than a year. I was thus able to assess it in right-hand-drive form, as Englishmen will buy it, the l.h.d. cars having all been non-starters but Sales-Link eventually having one of the latest versions available for us to collect.
Before writing further about this “new experience in motoring” let us look briefly at how NSU have contrived their largest and most significant model. The 1,990-c.c. twin-Wankel engine, which draws from side-mounted Solex 18/32HHP two-stage carburettors and has two sparking plugs per rotor, and which develops 113½ b.h.p. at 5,500 r.p.m. on a 9-to-1 c.r., is ahead of the wheels it drives, like the engine of a Lancia. It is mounted on four progressive-acting rubbers, augmented by telescopic dampers each side of the transmission casing. This unique engine is pump-cooled and has a torque-responsive fan and an oil-cooler. Electricity is generated by a 490-watt alternator feeding a 12-volt 66 amp.-hr. Varta battery. The electrics are Bosch.
This power unit drives through a Fichel & Sachs torque converter with a single dry-plate clutch operated not by a pedal but automatically by a Fichel & Sachs elector-pneumatic SM125 servo, to an NSU three-speed fully-synchronised gearbox having ratios of 9.984, 5.869 and 3.827 to 1 (reverse, 10.226). Drive shafts with homokinetic constant-velocity joints take the power, from a 4.857-to-1 drive unit, to the front wheels.
The body is of pressed-steel unit construction with box-section side- and cross-members. Suspension is all-independent, with McPherson coil-spring struts having a 7.4 in. travel at the front (wheel deflection, 188mm.) and the back wheels sprung on trailing arms and similar struts with a 10.12 in. stroke (wheel deflection, 257mm). The braking system uses ATE-Dunlop discs all round, 284 mm. dia. at the front, 272½ dia. at the rear, actuated by throw independent hydraulic systems, one circuit acting on all four wheels, the other on the front wheels. To reduce unsprung weight the discs at the front are inboard and to obviate the difficulty of getting an efficient parking brake with discs, the handbrake operates on 160-mm. drums on the back wheels. There is servo assistance of the main system and a load-dependent power regulator for the rear brakes.
Steering is rack-and-pinion, with ZF servo. Fuel feed is by diaphragm pump and although the very high standard off control makes the NSU Ro80 an essentially safe car, crash-precautions embrace a fuel tank located ahead of the rear wheels, a short steering column and a steering box mounted to absorb impacts, the aforesaid dual brake circuits and generous interior padding. If these enable you to survive, there is 360° accident warning lighting. The shape of the Ro80 is functional and has the very good claimed CW wind-resistance value of 0.355. There is a sophisticated heating, venting and cold-air system. There is an 18-months/18,000-mile warranty on the engine, a six-month/6,000-mile warranty on the rest of the car.
Driving the Ro80
The car that arrived at Standard House was a glacier white saloon, somewhat graunched along the n/s, with all-black interior. The appearance is just sufficiently unlike anything else to appeal, without being too eye-catching or unusual. The Wankel engine with its components and auxiliaries is as wide as a piston power unit but lower, and this helps the bonnet line. The initial impression is two-fold—the excellent all-round visibility from the large area of glass and the satisfying anonymity of the controls. This NSU is obviously intended for an owner who is prepared to sit down and find his way about the car before driving it and who is unlikely to lend it to all and sundry. For no ugly symbols, very little calibration, mar the neatness of the RRo80’s controls and instrumentation.
Wearing my NSU tie, I found myself sitting in a large, very comfortable driving seat which has an adjustable squab if a side lever is operated. (Height adjustment is mentioned but is not provided on r.h.d. cars.) The small steering wheel has three neat spokes and a padded hub and is free from cluttering controls. A stalk on the right operates two-speed wipers, powerful electric washers and, by pressing it down, the horn; a similar stalk on the left looks after lamps dipping, flashing, and turn-indicators. In other words, convenient finger action takes care of these vital items, once the confusing procedure has been mastered, which in other cars often call for the pressing or pulling of controls scattered about the facia. It is a characteristic of the Ro80 that common-sense has prevailed in laying out the controls. For instance, the lamps-switch is also, by turning it, a left- or right-hand parking-light selector, numerous different-coloured, very neat warning lights convey whether anything is amiss with the different services, and the four heat/ventilation controls in horizontal quadrants in the facia centre are easy to understand and supplemented by central fully adjustable fresh-air grilles and hot-air window demisting side vents. There is a back window demister as standard and a steering-column lock.
Reverting to the facia layout, a clever touch is the method of calibration on speedometer and tachometer dials, these covering three-quarters of each dial, thus obviating blanking by the spokes of the steering wheel. The tachometer reads to 8,000 r.p.m., with a warning segment from 6,500 r.p.m. above which speed the rotary engine may be run for short periods. These are Vdo instruments, with big, nicely-marked dials and steady needles. The 140-m.p.h. speedometer has total and decimal-trip mileage recorders. To its right is a Vdo Kienzle clock, to the left of the tachometer the thermometer and fuel gauge. The latter has a red segment for reserve, to which the needle is intended to point when petrol for about 60 miles remains; it is supplemented by a light which comes on when there is enough for approximately 24 miles. As driven, these signalled at nearer 95 and 40 miles, respectively.
The unidentified, spaced-out facia buttons are for choke, accident warning, cigar-lighter, fog-lamps/back windown demister, and lamps, plus a dual one which gives variable instrument-lighting (which goes to very dim but never right out) or zeros the trip mileage reading. There are pilot lights for nearly everything, including handbrake on/minimum brake fluid level and choke in use. The left of the facia is taken up by a reasonable-sized lockable cubby-hole. These neat instruments, unlettered knobs, plain facia decor, and black crash-padding for which the better German cars are noted. You step over sills into the Ro80, the floor is uncluttered, and moulded into the facia is a good grab-bar and a tiny oddments well.
There is conventional handbrake between the front seats and a big central gear-lever but only two pedals, on account off the automatic clutch. If a hand is laid casually on the gear-lever the drive is disconnected and terrible judders occur as the errant hand is withdrawn. This lever has five unmarked (apart from a screen stencil) positions—park, reverse, first, second and top. Left in top there is automatic transmission, at the expense of very sluggish pick-up from low speeds and much whirring from the torque converter, far removed from the car’s normal 0 to 50 m.p.h. in 9.9 sec., 0 to 60 in 14 sec. the two lower gears are held in and thus give the effect of a normal gearbox with a somewhat baulky change if used quickly. But the normal, as distinct from quadrant, movements of the lever are appreciated. I do not like this transmission, however, which is really the “Sportomatic” which has ruined the character of the Porsche. There is no need to have a torque converter with the Wankel engine, as Mazda has proved. I would like to drive an Ro80 with a good four-speed conventional transmission but, as a compromise for the World’s users, I accept that the present choice may be the wise one. But it is certainly a feature which makes the car nicer on open roads than in traffic, and even then the free-wheeling effect in top gear needs getting used to.
Indeed, it is in the wide open spaces that this remarkable NSU shows up so well. It will run up to an indicated 100 to 110 m.p.h. with consummate ease, the Wankel smooth as a turbine, and with no more noise than the rush of wind past the car, like a jet aeroplane in motion. In town driving there is noise from the torque converter and from the cooling fan.
But on long runs the Ro80 is a superb motor car. It has impeccable power steering. It corners unperturbably. It does this with lean rather than roll, and not protest from the clinging Michelin XAs tyres. The brakes pull it up powerfully with a minimum of effort. The turning circle is excellent, even surprising for a front-drive car of this size. The wheel asks 3 5/8 turns, lock-to-lock, and is accurate as well as effortless under power. As there is impressive acceleration to an indicated 90 m.p.h. in middle gear without taking the engine much above 7,000 r.p.m. and this speed in top represents 4,500 r.p.m., at our legal maximum the Wankel is scarcely running fast enough! The top speed, although I had no opportunity to check it, is in the region of 110 to 112 m.p.h., and 100-m.p.h. cruising is possible at 1,500 r.p.m. below the engine’s peak speed, so this biggest NSU is no sluggard, even if the 1200TT and the TTS NSUs can out-accelerate it. Maximum torque comes at 4,500 r.p.m. (117.2 lb./ft.), so it pays to keep the Wankel revving hard, as I discovered with the Mazda 110S.
Performance figures are not everything and the Ro80 is an extremely high average-speed car. Its phenomenal road-holding, its effortless, one might say unburstable, high cruising-speed, allied to comfortable seats and light controls, ensure that this is so. It is, in fact, a difficult car to assess; but one thing is unquestionable—its ability to compress big mileages into a short space of time and to do this without fatigue to the occupants and with a high degree of safety. I proved this on a most enjoyable run from Wales to Hampshire, during which the Ro80 climbed Birdlip at around 4,000 r.p.m. as if it were a speed hill-climb. Moreover, discounting the low-fuel warnings, I got an absolute range of 334 miles (from a tank which is said to hold 18 gallons, but which actually takes 16½), so too much time need not be wasted over refuelling.
The suspension is quite firm, causing body shake and rattles over rough roads, and it transmits road noise, but it gives a pitch-free ride. At speed over the bad surfaces the ride becomes choppy but the important thing is that the car still goes where it is pointed. The excellent power steering is free from kick-back and lost motion, has mild castor return, and is smooth but not too light, certainly not as light as that on a Silver Shadow. Then there are those splendid brakes, very light to apply, nicely progressive, free from squeal, and very reassuring at the speeds at which an Ro80 likes to be driven.
Apart from its ability to travel fast, the Ro80 has many refinements in keeping with its modernistic conception. The heater fan has stepless, not mere two-speed, control. Luggage-boot, engine compartment, and cubby-hole are automatically illuminated. The back seat squabs are removable to give through-space to the big boot for carrying bulky loads. There is a high-grade tool-kit in a box behind the spare wheel, containing one Beru, one Bosch plug as well as the tools. A very comprehensive instruction manual, and even a pricker for clearing a blocked screen-washer jet, were provided. These are in addition to more normally encountered items, such as sill interior locks, contoured arm-rests-cum-“pulls”, an anti-dazzle mirror, and external mirror on the driver’s door, pockets on the backs of the front-seat squabs, spare wheel on the o/s of the boot protected and strapped in, foam underlay for the velour-nylon floor carpets, roof grabs, coat hooks, roof lamps front and back with courtesy-action from the appropriate doors, dual silencing and exhaust systems, undersealing, hand- or electrically-operated sliding roof as an optional extra, etc. Upholstery is in black imitation leather and, applied to arm-rests, door handles, etc., adds to the air of quality.
The dual Hella headlamps give a fine driving light but the sharp cut-off makes night driving murderous. The deep anti-dazzle vizors, retracting into recesses in the roof, both have vanity mirrors, which makes the driver’s less adaptable to its proper purpose. The efficient ventilation arrangements call for no quarter-lights. The recessed internal door handles, stainless-steel wrap-round bumpers and lockable fuel-filler cap and fly-deflector on the o/s wiper blade are further refinements, and fuses accessible within the cubby-hole another example of the commendable attention to detail. The r.h.d. cars have four round headlamps, and no fog-lamps as standard. The test car had those excellent Britax reel-type safety belts.
The bonnet is rear-hinged but has to be propped up. The dip-stick and oil-filler are well placed. The instruction books says that “the oil consumption is nothing to get exciting about”, but I was more alarmed than excited when the oil-warning lamp started to blink before I had driven 400 miles! Examination of the dip-stick after the car had been standing overnight, so that oil had had time to drain into the “oil pan” as instructed, showed practically nothing, and to restore the level required half-a-gallon of Castrolite. A further check gave a consumption of less than 200 m.p.p. so the Ro80 is an expensive car to run, especially as fuel consumption on a fast run followed by London work (when the two-pedal control was appreciated) came out at 20.1 m.p.g., and the overall consumption was 19.3 m.p.g., although there is the balancing factor that the Wankel consumes petrol with an octane rating as low as 90.
Then engine starts promptly, hot or cold, and idles at 1,300 r.p.m., or at about 600 r.p.m. when held on the torque converter.
There are more comfortable cars, the Silver Shadow rides better, there are faster cars. But on all-round merit the NSU Ro80 must be rated one of the best family cars in the business. The price in Britain is £2,250.—W. B.
An Owner’s Views of the Ro80
[We have been fortunate in obtaining the following article by a discerning motorist, Mr. B. Webb Ware, on what it is like to be the private owner of a Wankel-NSU in this country. This gentleman wrote for our “Cars I Have Owned” series in 1941 and has had personal experience of M.G., Frazer Nash, B.M.W., Rover, Riley, two Healeys, Aston Martin, Fiat, VW, Volvo, Porsche, Simca, Mercedes-Benz, and a couple of Lancia Flavias.—Ed.]
After reading all I could lay hands on about the Ro80 I had a good look at the right-hand-drive version at the last London Motor Show. Tony Brooks agreed to get a demonstrator up to try. We met at Weybridge and I was a bit taken aback to find the car was left-hand-drive. Tony Brooks took over first and we tried some of the Surrey secondary roads. Only the fact that I had been driven by him several times before and kept saying to myself “This chap has won several Grands Prix”, kept me from going up the side of the car with anxiety, but as a demonstration of what an Ro80 could be made to do without effort, it was fantastic.
Taking over myself, one or two things seemed queer, quite apart from the strangeness of left-hand-drive. You stirred the gear-lever around in a vague effort to find a gear, rather like an elderly Renault which I once hired in Portugal, and the vacuum-operated clutch was very much in or out. There was no question of taking it up gently. Also she rolled a bit and there was an odd indefinable delay in the steering, so that in effect she answered to the helm! Peculiarly the one thing that did not seem strange was the Wankel engine.
Back at the garage we had a small council of war. Potentially the whole idea of the Ro80 seemed so good that it was rather a pity to judge solely on the demonstrator, but all the same I had an inward feeling of being a fool at parting with the two-and-a-half-year-old Mercedes 250SE, which had never given a moment’s anxiety in 28,000 exemplary miles, for a potential problem child. Also I was not sure I would like a white car, but was sure that I would not put down another £90-odd for a semi-non-standard colour.
Delivery was promised in two months, but took three. Admittedly I had complicated things by stipulating a power-operated sunshine roof, after enjoying this boon to life in the Mercedes. Highly coloured and apparently authentic information came in at intervals of the passage of the car from Neckarsulm across Europe and the North Sea to Shoreham, only to be completely contradicted by news that the car had not yet left the works! My family also made their view clear that selling the Mercedes was an act of sacrilege, so I was in a critical mood when it finally arrived.
Now five weeks and 1,600 miles later, I can’t claim extensive experience of the Ro80, but I am completely won over and—even more important—so has my wife been, who is liable to be a stern critic after the two Lancias and the Porsche which preceded the Mercedes. This also despite the fact that it gradually dawned on me that something very odd was wrong with the ZF power steering. The sequence of events was that when you started full power was there. After three miles assistance began to drop off. After some twelve miles, assistance was down to only a fraction. Switching off the engine brought back full assistance for a few hundred yards. Before recognising that this was happening, I had been critical of shocks feeding back through the steering, rather painful to an arthritic hand. I got hold of one Peter Ing at Shoreham on the phone, and whatever might have been the delivery shortcomings he was first rate on servicing. On the cheerful principle that although he had never met this fault there always had to be a first time, he had her back on a day when he was trying to cope with the unscheduled delivery of about a score of Ro80s, diagnosed a fault on the pump pressurising the system, got on to the pump manufacturers and traced an intermittently seizing piston valve, and let me have the car back, all in the one day.
Criticisms? Typical of right-hand-drive conversion cars, the windscreen wiper blades have not been changed and leave a blank unwiped quadrant on the driver’s side. Equally, the demisting works quicker for the passenger than the driver. The catalogue advises that the driver’s seat is adjustable for height. Well, if the adjustment is there I’ve not found it. Due to sealing, the doors have to be slammed, instead of the well-bred “clunk” of the Mercedes. Are the bumpers stainless steel? They may be, but they look like chromium plate to me. You can beat the synchromesh on a change up, and in open traffic, approaching a roundabout for example, you have to realise that the engine does not give the braking on the over-run of a conventional four-stroke and accelerate deliberately on changing down. You have to match this rather more precisely than one is used to, because of the clutch operation characteristics. Petrol consumption of 21 m.p.g. overall is perhaps not good for a 2-litre and it definitely needs one pint of Shell 100 every 300 miles.
But in place of some of the handling oddities of the left-hand-drive demonstrator, the gear-change on my Ro80 is pleasurably precise, the power steering delightful. Starting any morning is certain in an unheated garage with an application of the choke, that can be released within seconds. Now that I have identified an irritating rattle to one of the bonnet catches and cured it by application of Selotape round the rotating pin on the catch and I know that a musical squeak on the discs only applies while reversing out of the garage, and that a slight whine in the steering is due to the fit of the plastic bush at the top of the column, I do revel in this unique car. Its visibility is first class. Once found, the seating positon is just right for my long legs, and I do not mind if the suspension makes me more conscious of the road that I was in the Olympian detachment of the Mercedes.
Above all else, the NSU Ro80 has an endearing “magic carpet” quality of getting to the journey’s end quicker than you expect. You can drive it as if it had a conventional three-speed box. You can drive it more or less like an automatic with the great saving grace that you can hold any gear, instead of watching it change down and spin helplessly in snow or on mud, or you can play silly tricks for fun, like staring in top, revving up to 3,000 r.p.m. and then holding the revs while the car accelerates at constant engine speed. Above all there is this seductive engine note—not silent, but getting quieter and smoother with speed. If I am clear of teething troubles and long-term reliability matches present qualities I shall be very satisfied.—B. W. W.