German high performance
Motor Sport visits the BMW and Porsche factories and tests representative models
On arrival at Stuttgart Airport last month, we found awaiting us a maroon Porsche Carrera and a grey Porsche 1,600. The Editor was put into the Carrera, his colleague drove the 1,600, and thus we arrived at the Porsche works in the pleasant factory suburb of Zuffenhausen.
The rear-engined, air-cooled flat-four Porsche is now well and truly established as a compact, beautifully-proportioned high-performance car—in fact, there is no other car quite like it.
So effective is the Porsche body-shape that any change would detract from optimum aerodynamic efficiency, which is why, outwardly, it is almost impossible to distinguish a 1,600 from a 1,600 Super, or these models from a Carrera.
Coming from a country where, although considerable enthusiasm exists for limited production sports car, the firms that produce them are very small indeed. It was heartening to find the demand so great. that 700-750 workers are employed in building 20 Porschesa day. They work under conditions normally associated only with a racing-car factory, the benches and floor in the one big assembly hall spotlessly clean and skilled labour employed for the more complicated of the assembly processes.
We were conducted round the compaet factory by Fritz Huschke von Hanstein and his assistant Dr Hortolf Biesenberger. whose efficient manipulation of visiting journalists matches the efficieucy encountered in all departments of the Porsche organisation.
The Porsche is essentially a specialised hand-built motor car. The customer orders one of the three basic models-coupe (with or without sliding roof), convertible or open Speedster he requires, specifies either a 1,600, 1,600 Super or Carrera engine, and finally decides on such details as colour of body, type and colour of upholstery, make of tyres etc, and then and then only is a car prepared for delivery to him.
In an age when a sports car is often endowed with a mass-production power unit borrowed from a bread-and-butter model and has many major components which emmanate from the same source, a visit to the Porsche factory is like a breath of cool, clean, air—the air of enthusiasm taken to the pitch of near-perfection. Half-measures do not get a chance at Zuffenhausen.
For example, before an employee is engaged he has to serve a four-year course at the factory as an apprentice, attending three or four lectures a week given by senior executive of the company and learning thoroughly the Porsche methods. These apprentices work at one side of the factory, preparing supplies of components for the assembly line and undertaking other comparatively unskilled tasks. Only when they have qualified are they employed on car assembly or sent out as Porsche service representatives.
The layout of the Porsche assembly line is simplicity itself. In the. well-lit, spotlessly clean assembly hall the body shells arrive on trolleys from the adjacent Reutter coachwork factory. They then proceed along a U-shaped assembly line, the suspension components and detail fittings being attached as the cars move along the first leg of the "U" the power units and components being added as they progress along the remaining leg, until complete cars, ready for road-test, emerge side by side with the body shells entering the factory. Each stage of assembly occupies 22 minutes, as skilled fitters and mechanics go about their tasks, after which the car is moved on to the next station, for the next operation towards completion.
Beside, the assembly line is the engine assembly bay, the engine crankcase being held in a rotatable jig running on a waist-high rail, so that as each step in engine assembly is completed the jig can be rolled along to the next fitter on the line, the entire unit being turned over as required. Six or seven fitters build up each engine. Castings are supplied by a local foundry but women are set to work on them with electrically-driven wire brushes, polishing ports and smoothing the insides of the manifolds before assembly. Pistons are warmed on electric stoves. to ensure the correct relationship of expansion between piston and rings before they are inserted in the cylinder barrels. When each engine is completed it is taken on a trolley to a test-house outside the assembly hall and run on one of a pair of Schenck-Waage water dynamometers for a period of four hours. In this test-house there is no evidence of noise, heat or fumes, but here every engine note, every engine—is thoroughly tested, an hour's running being done at 3,000 rpm, followed by half-an-hour idling, then 11/2 hours at 5.000 rpm, followed by a final half-hour of fluctuating throttle openings. A book is kept in the engine test-house in which full details of each test are entered, atmospheric pressure and air temperature at the time being first recorded. At the end of the test period a horsepower check is taken and any engine which does not come very close to normal is stripped down for examination by a staff separate from the fitters who assembled the engine. This is not the end of Porsche testing, because every car is driven on the road for one hour.
It is taken as a matter of course that wheel-balancing, a micrometer check of tolerances in roller-bearings for the gearbox etc, and a final test that the front wheels are correctly aligned, are undertaken.
The staff works from 7 am to 5.30 pm five days a week and the racing staff all hours of the day and night as required. Incidentally, tools have to be drawn from the stores, signed for each morning, and handed in at night and the spotlessly-clean spanners, etc, are laid out on the benches like surgical instruments.
We had only been in the factory for matter of minutes before our eyes alighted on a battery of 16 steering-boxes being motored electrically, from full-lock to full-lock, a process which goes on for some three hours (equal to 3,500 miles' driving) to ensure a perfectly smooth steering action when the customer drives away in his car.
The U-shape assembly line, from which issue 20 complete Porsches a day, has been described. Beside it is a bay, in which stood three cars at the time of our visit, where customers' special items of equipment are fitted.
Porsche uses Bosch electrics, Solex carburetters (Weber on the racing models), and Vdo instruments, the speedometers calibrated in mph or kph as required. Tyres are anything the customer desires and we saw Dunlop GT, Continental, Firestone and Metzeler covers awaiting fitment. The seats can be upholstered in a variety of colours, with leather or corduroy inserts, and if a customer fancies lightweight racing seats in a normal coupe these are fitted as his car moves along the assembly line.
We were shown the nicely-finished crankshafts and camshafts and when Dr Biesenberger asked a fitter to show us a Super crankshaft this was reverently presented in a cardboard box, covered in greaseproof paper, in which these beautifully finished components are stored until required for assembly in the crankcase. The specification of the Porsche is too well known to merit repetition, beyond reminding readers that three engine types are available, the 1,600, the 1,600 Super, and the 1.500 Carrera. The engine dimensions are : 1,600 and 1.600 Super, 82.5 by 74 mm, 1.582 cc; Carrera, 85 by 66 mm, 1,498 cc. The 1,600 engine has a compression-ratio of 7.5 to 1 and gives 60 bhp (70 SAE) at 4:500 rpm, using Solex 32 PB1C carburetters. The 1,600 Super engine develops 75 bhp (88 SAE) at 5,000 rpm on a compression-ratio of 8.5 to 1, using Solex 40 P1CB carburetter. and a crankshaft with roller-bearing big-ends. The 1.500 GS or Carrera engine was developed from the Type 550RS engine of the spyder and is a very advanced unit with four oh camshafts, all-roller-bearing Hirth crankshaft, twin-choke Solex 40 PJJ carburetter, two-plug heads, twin cooling fan, dry sump lubrication, and a compression ratio of 9 to 1. It develops 100 bhp (115 SAE) at 6,200 rpm.
The original 1,300 engine, of 74.5 by 74 mm (1,290 cc) can still be supplied if required. It gives 44 bhp (50 SAE) at 1,290 rpm on a 6.5 to 1 compression-ratio, or 60 bhp (71 SAE ) at 5,500 rpm in Super form, with 8.2 to 1 compression-ratio etc. The Spyder open model, with Carrera 110 bhp (125 SAE) engine, was discontinued after 100 of this model had been made. The basic Type No of all the production cars is now 356A. Few changes have been made to the specification of these remarkable little cars since the steering geometry was redesigned some time ago to reduce to a minimum the violent oversteer formerly associated with the rear-engine layout, the shock-absorbers being mounted vertically instead of at an angle at this time. A new soundproof material is now employed to upholster the roof of the coupe, and short funnels now feed warm air to the carburetters in conjunction with the normal thermostatic temperature control of the cooling air, the funnels terminating, however, a long way from the air-intakes.
If Americans are a familiar sight all over modern Germany, this is perhaps of benefit to Porsche, for 52 per cent of their output is sold to US customers, for whose requirements special items of detail equipment were introduced. Total exports represent 70 per cent of production and over 10,000 Type 356 Porsches have been built.
After we had been shown the factory Dr Biesenberger asked which cars we would like to try. We decided to take away the Carrera, returning it late on the Saturday afternoon to exchange it for a normal 1,600 coupe, and borrowing on the Monday a 1,600 Super for comparison. Nothing could be easier—in a few minutes insurance documents were in our hands and we were off on a long test of the fastest normal Porsche model.
Outwardly the Carrera is distinguishable only by its twin exhaust pipes and the name on the side of the body, but a glance at the instruments reveals that the switch operating the screen-washers on normal Porsches is for the fuel pump (a foot-operated washer being substituted) and that two extra ignition switches are fitted for testing separately the two sets of sparking plugs. There are also some fascinating markings on the rev-counter, "the red" being at 6,500 to 7,000 rpm ! Lifting the rear boot-lid reveals the exciting engine, with twin Bosch distributors, fed by two Bosch coils driven off the back of the upper camshafts, and the smooth fan cowling reminisant of the cowl round a radial aero engine.
To describe in detail the many sensible, practiral and therefore acceptable items of a Porsche outside the space-scope of this account, but these aspects include a rear seat folding to form a luggage platform, with straps for securing cases and loose items, lamps-flasher in the steering-wheel centre, special arrangement of ventilators and door locks, reserve petrol tap, heater knob adjacent to the gear-lever, seats with adjustable squabs which fold to form beds, etc, were described in Motor Sport of last February, page 77, while a full account of motoring a Porsche 1,500 for 30,000 miles on the Continent will be found in Motor Sport dated December, 1955.
Let me proceed to tell you how we enjoyed this Carrera, shod, incidentally, with those excellent Continental "Record" 5.90 by 15 tyres, and with Sigla safety-glass in all the windows.
Leaving the pleasant town of Stuttgart, with its yellow trailer-trams, which draw current from overhead gantries, and the vast yellow buses, we took to the autobahn for some preliminary investigations. The next morning we got down to it in earnest, filling up with BP Super--forecourt service, by the way, is a feature of German garages—at the beginning of the autobahn to Munich, where a Citroen Six with two-door drophead body and a vintage flat-twin Tatra were our companions. No oil was to be needed for the engine but, had it been, Porsche asked us to use Castro!.
Before the war motoring scribes used to come home to tell of sensational average speeds set up along the German autobahnen, to their personal satisfaction and the consternation of the manufacturers whose cars they had been thrashing. Today the story is rather changed, because bridges blown up during the war are still under repair and on the road we used there were other two-way stretches where normal repairs were in progress. In addition, a long climb up a ravine is also a two-way road, although a new one-way section will soon be completed. Here, no-passing is the strict rule and as gigantic German lorries and vast (which is a mild term !) USA tank-transporters proceed uphill and down at about 3 mph, with frequent halts, you need a fast car to return good speeds. On that Saturday morning there was heavy traffic about, so that we could not average better than 88.2 mph for 188 kilometres, incidentally, this was stop-watch timed against the kilometre posts. The Carrera, although it was still rather stiff, proved happy cruising at 100 mph, and its maximum speed was about 120 mph, or 5 mph down on a fully run-in car. 200 kph equalled 6,700 rpm on the rev-counter and the oil temperature on this sunny morning never exceeded 80 deg F, which provides an answer to Mr Storey, writing in the last issue.
There is a real punch-in-the-ribs as the throttles are opened in the gears, and the engine emits a hard power-roar above 5,000 rpm, although normal conversation is possible as you motor along at 100 mph.
We clocked some acceleration times, without being brutal to the engine : to 50 mph. was accomplished in 8.8 sec, to 70 mph in 15 sec, while the power available in the upper engine-speed ranges is indicated by a figure of 30.3 sec to go from a steady 3,000 to 5,000 rpm, 4,000 to 5,000 rpm taking 15.4 sec, and 5,000 to 6,000 rpm a matter of 34 sec, top gear being used in each case (6,000 rpm was equivalent to approximately 107 mph).
The Carrera handled in typical Porsche fashion, over-steering, but not excessively, the steering requiring 31/2 turns, lock-to-lock. The seats are exceedingly comfortable, providing the support needed in a car of this performance and manoeuvrability, with generous leg-room.
After driving through Munich, where there are more trailer-trams, but painted blue, and where parking meters are again in use—a foretaste of what London will "enjoy"—the Editor relinquished the stop-watch and drove back along the autobahn to lunch at Ulm in the shadow of the famous cathedral.
We arrived at the Porsche factory late on the Saturday afternoon, but although the works was closed as we came up to the electrically-lifted bar across the entrance, a gate-keeper who had been sitting in the sun outside his office jumped to his feet, waved us in, and in a matter of minutes we were on our way in a normal Porsche 1,600, equipped with more insurance documents. This car we were allowed to use over the rest of the weekend. It was equipped with Metzeler 5.60 by 15 tyres, had the new warm-air funnels to the carburetters, a Fram oil-filter and, of course, a single exhaust tail-pipe.
The 1,600 normal or "Damen" Porsche is naturally quieter than the Carrera, which, again, is noisier than a Super. It had rather heavier steering but the same gear-lever, which, in conjunction with the special Porsche synchromesh designed by Leopold Schmid (which is used not only for the cars but for lorry gearboxes with 10 forward speeds designed for an opening torque of some 651 ft/lb), makes gear-changing an absolute delight, whether the driver wants to go from third into top or second into bottom gear.
Getting up early on the Sunday, we drove along back roads through beautiful country to lunch in the open air at Weissensee, having sampled this silver-grey Porsche on a run beside the river Neckar to Heidelburg the previous evening. For the most sober model of the range, giving a petrol consumption of considerably better than 30 mpg, the performance was certainly impressive. It cruised at 100 mph (4,700 rpm) for miles along the autobahn, the oil temperature again never exceeding 100 deg F, although being higher than on the Carrera as wet-sump lubrication is used. 0-50 mph was accomplished in 10.6 sec, and 0-70 mph in 20 sec, while in top gear it was possible to go from a steady 3,000 to 4,000 rpm in 17 sec, and from 3,500 to 4,500 rpm in 20 sec.
After lunch we drove almost to the Swiss border, being unable to cross the frontier as we had no carnet for the car. Summer had come at last and the roads carried a long stream of cars in both directions, so that the Porsche's desire to climb up the Kesselburg with verve had to be curbed, and it was with relief that we returned along a very beautiful forestry road (toll 4s.) beside the Walchen-See, amid Bavarian seemery beautiful beyond words. a fitting finale to an afternoon of twisting and turning under the awesome presence of tall snow-tipped peaks. Getting into the Munich-bound traffic stream before joining the autobahn, we were impressed with the manner in which everyone drove at 60-65 mph along a winding road with a drop into fields on either side, faster cars making skilful use of any gap which appeared, and even more impressed by the carefree manner in which solitary oncoming vehicles also held 60-65 mph ! Once on the autobahn, however, it was rather a different story, mimsers keeping in the fast lane at the same speeds they had used beforehand. Away from the autobahn the 1,600 Damen proved a more useful car than the Carrera, which would have been almost permanently in second gear !
We covered 670 enjoyable miles in this version. The Editor kept an eye open for vintage cars, but they are as rare in Germany as they are prolific in France, where cars built before 1931 now go tax free. Apart from one early Goliath three-wheeler and one of the original BMW 3-15 (Austin Seven-type) saloons, the score was nil. We met only two Mercedes-Benz 300SLs, one at an "embarrassing" moment on a bend, so that, as its driver braked heavily, it went sideways-on ! Plenty of the exceedingly-attractive Mercedes-Benz 190SL sports cars were about. Of British cars the Austin-Healey is popular, we saw one German-registered TR2 hard-top, some MG MGAs, the odd Riley and Rover, two Austin Sheerlines (one occupied by a bishop !), and a smaller Austin stationary beside the autobahn with its bonnet open, and that was about the lot. The tiny Lloyds and Goggoomobils are now a normal aspect of the German scene and very reasonably proportioned and smart they look.
On the Monday morning we found ourselves at the large and imposing factory of BMW, with an appointment to meet the Sales Director at 8 am,--in Germany the working day commences at 7.30 for workers and directors alike ! This was rather like being at Coventry or Birmingham with a Cooper to return to Surbiton, but BMW rose to the occasion, lending us a chauffeur-accompanied 502 for the rest of the day and permitting us to drive it. The two cars motored in convoy back to Stuttgart, the 200 kilometres of autobahn being covered at an average speed of a fraction under 80 mph.
At Porsche's we found them happy over their Avus victory and Frankenburg's fortunate escape from serious injury. After a quick stroll through the delightful offices, where brightly coloured ultramodern furniture and decoration prevail and external striped sun-awnings shield the windows, and a glance at the equally-modern and airy lecture room, where sectioned Carrera engines could be studied. we were dispatched in a third Porsche—a green 1,600 Super, with twin exhaust pipes and Michelin X 155-180 tyres. In this the seats seemed higher, the wheel closer to the dash and the steering very light and sensitive. The deeper growl of the exhaust told of the greater power and a speed of just under 120 mph (5,500 rpm) was quickly reached, long curves being taken steadily at 105 mph. 0-50 mph occupied 9.8 sec, 0-70 mph a time of 17.4 sec, and it was possible to go from a steady 3,000 to 4,000 rpm in 24 sec, and from 3.500 to 4,500 rpm in 20 sec, in top gear. Only after these tests did the oil temperature climb and then not above 110 deg F.
We regarded this as an eminently satisfactory 11/2-litre motor car ! After some final photography we left the Porsche factory and set off for Munieh in the BMW. 502.
It may not be generally known that the present Zuffenhausen factory was not built until 1952, the Porsche originating at Gmuend in 1948 and being shown to the customers for the first time at the 1949 Geneva Show. This factory, where the first fifty Type 356 cars were built, was moved to Salzburg in 1950 and today is headed by Mrs Louise Porsche and is the Austrian headquarters of VW. Prominent Porsche personalities include Chief Engineer Karl Rabe; Erwin Komenda, who evolved the famous body-shape; Hans Kern the treasurer; Karl Kern, who manages the buying department; Walter Schmidt, head of sales; Klaus von Ruecker, late of Studebaker, who is head of the technical department; Dr. Ernst Fuhrmann, designer of the four-cam engine for the Carrera, of which over 100 have been delivered and of which a Gran Torismo version is on the way, and Wilhelm Hild, who looks after the racing department. The racing shop is separate from the main factory but the engines for the RS Porsches are tested on the normal test-beds. The drivers are engaged race by race, not signing a season's contract.
Besides; the inimitable Porsche car, Porsche engines have been used in aeroplanes and racing boats, tractors are built in the Porsche diesel engine faetory at Friedrichshafen under Prof Albert Prinzing, and much outside design work is undertaken. The tractors have engines of one to four cylinders, developed from the first 12-hp and 17-hp, and later AP22 models, after the first batch had been lost in the OM factory at Brescia during the war.
Reuter commenced making Porsche bodies in 1950. After Dr Porsche's death in 1932 his son, Dr Ferry Porsche, took charge.
The comfortable and spacious 2.6-litre V8 BMW, running on Dunlop "GT" tyres, cruised at a timed 100 mph, its speedometer "spot-on" at that speed. In spite of stopping to extract the uninjured occupants of a Mercedes-Benz 220 which overturned in front of us on to the opposite lane of the autobahn in avoiding a swerving lorry --lorry drivers go to sleep frequently on these fast, monotonous motor roads ! --we averaged approximatly 72 mph. Where in England could you do that between two major towns 125 miles apart ? When the brakes of the BMW were required they proved exeeedingly powerful. "But they judder," we said. The chauffeur, who hadn't much English, then tapped the mileometer to show us the car had done 58,000 kilometres ! A fuller report of the BMW 502 appeared in Motor Sport for November 1955.
BMW are now producing 20 to 25 cars a day, mostly 501s and 502s, and two or three 503s a day, while the 507 sports/tourer is now in production. Seven thousand workers are employed, although some were stood off recently and short-time working, from 7.30 am to 3.30 pm, for five days a week is in progress. Production of the little Isetta "bubble car" has been cut from 200 a day to 140-150 a day. The beautifully-finished, shaft-drive BMW motor-cycles. first built in 1923, are still made—single-cylinder types R25/3 and R26 and the flat-twin R50 and R69, and R60 combination. They are exported to 90 countries, but demand is falling as the Isetta takes over.
Car production started about 1928 and aero-engines followed. In the vast entrance hall is large model of a BMW 501 and two record-breaking motor-cycles, as well as a 1923, 1930 and early racing motor-cycle can be studied.
The 501 and 502 are beautifully made and appointed saloons, the 501 normally a 2-litre six-cylinder but available with the 2.6-litre V8 engine, while the 502 has either a 2.6-litre or 3.2-litre V8 power unit. All models have torsion-bar suspension, with normal back axles. The 503 is the fast version. with 3.2-litre V8 engine, the two-door saloon having electro-hydraulic window actuation, used for the hood also on the convertible model. The 501 and 502 engines have a single carburetter, the other engines two carburetters. The 2.0-litre V8 engines, which do not give quite as much power as the others on the bench, are reserved for the 501, such engines probably gaining the lost power when fully run-in. The 503 -and 507 engines differ from one another only in respect of higher valve lift and polished cylinder heads, the 503 giving 140 bhp at 5,200 rpm and the 507 developing 150 bhp at 5,500 rpm, while both units give 23/4 metres/kg torque at 4,000 rpm. The 507 runs safely up to 5,800 rpm, and has a power/weight ratio of 8.4 kg per hp. All 2.6-litre cars have unfinned brake-drums, the 3.2-litre cars have stiffening fins on the periphery of the drums, white the 503 and 507 have German-made Alfin drums. The suspension torsion-bars run parallel to the side-members of the wide chassis, being considerably longer for the back wheels. Externally the 2.6 and 3.2-litre 502 engines are identical.
The BMW factory is pleasantly situated opposite a club aerodrome on the fringe of Munich, the buildings, which are not overshadowed by tall chimneys or housing estates. covering an area of 91 acres. The clean, well-lit halls cover complete engine building, chassis assembly and body construction. The foundry is famous for its light-alloy castings, which are also produced for outside concerns. The 501s and 502s go through in batches of standard colours but each 503 has to be ordered in the colours required. Much use is made of neon lighting, even along the production lines. Vast Weingarten presses are in evidence, the biggest being of 1,350 tons, Smaller Muller and Schuler presses are used and a huge over-head gantry crane distributes castings about the hall. The bodies travel on rubber-tyred trolleys, being rubbed down after the first coat of paint.. The final finishing bay is fascinating, every body being carefully inspected under powerful lamps and hand-polished, which goes for Isettas as well as for BMWs. Every 10 minutes a body emerges from the paint shop, in which Schilde drying ovens are used. Incidentally, operatives are supplied with the inevitable Coca-Cola as well as milk.
The finished chassis are Tecalemit greased and a 500-kg overhead gantry conveys power units to the assembly lines. Every two-piece propeller-shaft is electrically balanced on a Hahn and Kolb machine. Radiators are supplied by Kublerfahrik. Even the Isettas have their headlamps adjusted before they are passed out, Isettas without the rear window are used in the factory to carry Varta batteries and supplies of various makes of tyres to the single, long Isetta assembly line.
The last shop we visited was the new engine and transmission hall, beyond the foundry. This is a maze of costly machine tools as far as the eye can roam --Fritz Werner drills, Gillemeister horizontal drills, batteries of Stachely gear-cutters, Gleason gear cutters, Wanderer lathes and a new Hurth machine of which no man yet knew the object. At one side of this hall engine testing took place and, although not enclosed, sound and smell were virtually absent. Every engine-note, again, every engine----is tested on a Schenck water-brake, six-cylinder 501 engines for three hours, 501 and 502 V8s for six hours, and the 503 V8 for ten hours. A record is kept of the output and performance of every engine, while running road conditions are simulated by blowing air on to the sump and maintaining the cooling water at natural temperature. Isetta engines are only run for a short time but each Isetta goes for a test run round the grounds. The 507 engine is likely to be run for 20 hours. Road testing covers 20 to 30 kilometres for each 502 and 100 kilometres for each 503. Once upon a time a banked motor-cycle test track existed in the grounds, but it has been dismantled.
Of the finished cars, which included very handsome 503s in two tones of green, cars were ready for dispatch to places as far apart as Vienna, Caracas, North America, etc.
The 502 remains unchanged, although an under bonnet lamp is an extra refinement. The Isetta now has the hand-brake on the off-side wheel-well and the brake fluid reservoir on the floor beside the battery. They are made in two engine sizes, 68 by 68 mm (215 cc) and 72 by 73 mm (295 cc). the larger.engined model distinguishable because "300" appears on the door after the name.
No storage park is maintained for the cars but Isettas were liberally sprinkled about the grounds. In one park an early BMW prototype small car, a prototype of the 507 and a Citroen DS19 bought for experimental purposes were encountered. Rumour sounds faintly of a slightly bigger, wider track version of the Isetta, fanned when a little Isetta lorry with equal front and back track shot past.
The culminating point of our visit was being permitted to sample a 503 saloon and the prototype 507. The 503 is an exceedingly handsome car. with pleasingly narrow radiator grille. The car we went out in was in two-tone blue. and the finish of the. body and high-grade leather upholstery was fully up to German standards, for they are masters of the art of body-building, especially convertibles. The driver has control of all four electro-hydraulic windows those in the doors sliding conventionally, the quarter-lights arcing into the body sides, but the passenger has but one finger-slide actuating the windows on that side. Speedometer (reading to 240 kph) and rev-counter (6,000 rpm, with red marks from 5,7500, to 6,000 rpm) occupy a cowled panel immediately before the driver, fuel gauge and water thermometer living incorporated in the rev-counter dial. Traps normally cover the screen hot-air vents. The gear-lever is on the right of the steering column (lhd car), with umbrella-type hand-brake beneath the dash. Each door has large and small elastic topped pockets. The four-spoke steering wheel of narrow "X" formation has horn pushes across the spokes. The rear compartment was rather cramped for a person of average stature. The car had Continental Super 6.00 by 16 tyres. Being new and stiff. we took no figures, but the handling qualities and brakes proved first class. No German journalists had driven a 503, which, incidentally, has to be returned to the factory for overhaul.
The impressive 507 had 6.00 by 16 Conitinental "Record" tyres and knock-on hub caps to steel disc wheels, which are an extra on either model. Both have unobstructed luggage boots, that on the 503 very spacious: the spare wheel is carried under the floor in each case. A pleasing aspect is the use of torsion-bars for boot lid and bonnet ! The 507 had a large full-width screen, excellent hood, and an experimental cold-air feed from a shallow bonnet-top intake to the twin carburetters, rubber sealed. Axle ratios of 3.7 and 3.89 to 1 are available for the 503, 3.4. 3.7 or 3.119 to 1 for the 507. All 503 and 507 engines have twin carburetters and compression-ratios of 7.5 to 7.7 to 1.
This very handsome "Fahrleistung Wagen 507" is intended as a sports, touring car. BMW realising it isn't fast enough for competition work. Nevertheless, it has a splendid performance. Von Faulkenhausen let us take the following figures: 0-50 mph in 5.2 sec, 0-70 mph in 10.2 sec, 3,000 to 4,000 rpm in 11.8 sec, 3.500 to 4,500 rpm in 16.1 sec, in top gear, hood down. With the hood up we accomplished 3,000 to 4,500 rpm in 19.6 sec, 3,500 to 4,500 rpm in 14 sec, and 4,000 to 4.500 in 20.6 sec, using top gear, which, on this car, was equal to 21.8 mph per 1,000 rpm. 125 mph was reached easily in open form, which is the maximum with the large screen, but with the hood up this unproved to just over 128 mph. Obviously, higher speeds would be attained on the 3.4 to 1 axle ratio, given a long run, and even better acceleration on the 3.89 to 1 axle.
The roadholding along a splendidly winding road before reaching the autobahn showed up the splendid roadholding of the 507. It has a normal four-speed gearbox controlled by a very short, stiff, large-knobbed central lever, which tended to jump out of second and top gear. The car weighs 1,310 kg empty, compared with 1,600 kg for the 503, and its wheelbase measures 8 ft 31/2 in. We were unable to check fuel consumption but von Faulkenhausen produced the most comprehensive data sheets for the car, even to figures showing what percentage of power could be used on various road surfaces without spinning the wheels, the maximum gradients climbable in the gears (10 per cent hill in top at nearly 100 mph, to 32 per cent hill in second at 50 mph), and speeds in gears. From this we read fuel consumption of 2.042 kg per hp hour at 4,000 rpm on the bench and 8 litres per 100 km at 50 kph in open form on the road, or 10.1 litres at 100 kph, 16.5 at 150 kph, and 25.0 at 190 kph. The engine peaks at 5,500 rpm and is safe up to 5,800 rpm. The power/wt ratio of the 507 was given as 8.4 kg per hp, and its average speed for a ss kilometre as 122.7 kph, or roughly 77 mph,
Porsche RS seats can be fitted to the 507 if required. It will sell for about £2,650, and a quickly-detachable aluminium hard-top will be available for approximately £150 extra. Although BMW appreciate that the 507 is not sufficiently fast for sports-car racing, with its very good performance, excellent gear-change and outstandingly safe roadholding it constitutes a very handsome sports/tourer. Von Faulkenhansen hopes to drive one in the 1957 Alpine Rally.
Our few days in Southern Germany came to an end and soon we were being flown back in a comfortable BEA Vickers Viscount. There were two interesting English links at the factories where we were so graciously received—John Cooper had spent 11 days at Porsche's (your guess is as good as ours !) and BMW have supplied a 2.6-litre two-carburetter 130-bhp engine to AFN Ltd.