N nothing is more convincing than a practical attempt . Have you ever heard of the legendary smoothness of a Knight slide motor? But never the engine itself, because the automobiles with the Knight units are among the species that are almost extinct? Then just follow me to the black and blue Panhard et Levassor 20 CV Sport that is parked over there behind the fountain.
The sportiest car in the Panhard model range from 1929
Incidentally, you should praise the condition of the Panhard & Levassor 20 CV Sport. Even if the roof leather of the faked convertible top with its non-functional tensioning straps looks a little cracked and brittle, even if the paint only has the dull charm of an ancient touch-up, even if the cloth covers of the seats tell that the mouse and moth are already at the table and found a bed: Here is a car that has survived three quarters of a century without restoration or major technical interventions. And which will probably still run with the first set of pistons.
The start ceremony of the Panhard & Levassor 20 CV Sport requires a little patience and knowledge, because it starts with opening the right bonnet. You can see from the inside that the Janssen bodywork company, which works in Levallois, was not satisfied with the chassis that Monsieur André de Neufville had delivered from Panhard et Levassor from the Rue de Varennes in Paris, back in the spring of 1929. The pre-assembled hood had to be installed extended a few centimeters. Because Janssen moved the bulkhead a hand's breadth backwards in order to design a body that didn't appear too bulky on the short wheelbase of 2.70 meters. The Panhard & Levassor 20 CV Sport was ultimately the sportiest car in the Panhard model range from 1929. A long hood and a shortened passenger cell simply went better with the sporty look. But I digress. We wanted to start.
Carburettors, which are switched on when required
You may have noticed the little yellow funnel dangling there next to the fuel filter. This is now needed, because the silver container above the filter, which looks like a metal canteen, can now be filled with a good shot of gasoline from the canister. The Panhard & Levassor 20 CV Sport does not yet have an electrical or mechanical fuel pump, so when the engine is running, a right one kicks inHand flanged, small compressor, the tank in the rear under pressure. The gasoline is then pneumatically pressed into the triple carburetor. Incidentally, it comes from Panhard production and bears the same number as the X-56 engine.
Panhard, you must know, set up highly standardized industrial production as early as the 19th century. The middle carburetor of the Panhard & Levassor 20 CV Sport, it has the same number as the engine, is for low speeds. But if you want to go faster, the depressed accelerator pedal also opens the two outer mixture factories. To do this, the engine has to be running first. The liter of fall gasoline from the small, round additional tank floods the carburetor even without excess pressure. Open the large fuel tap on the left of the instrument panel, and then press the start button hidden behind the clutch with your left foot. The starter flanged to the front of the crankshaft struggles, it's cold and the four cylinders are still not getting enough ignitable mixture. Short break.
The starter and alternator of the Panhard & Levassor 20 CV Sport form one unit. When the engine is running, the starter turns into a generator and supplies power to charge the 12-volt battery in the rear. Dynastart is the name of the system that Steyr-Puch, for example, used until the 1970s. The second attempt is crowned with success. The Panhard & Levassor 20 CV Sport is still limping in idle, but with increasing temperature and a sensitive turn of the knob and toggle for mixture and idling, the Panhard & Levassor 20 CV Sport will soon run as smoothly as the chain carousel next to the Eiffel Tower what can be heard? First the friendly drum of the exhaust. After all, the flap, with which the exhaust gas can be released to the outside by pressing the pedal on long-distance routes, no longer seals completely after all these years. The whispering noise of the radiator fan is hardly noticeable next to it, and the mechanical noises of the engine can no longer be heard from a step away from the Panhard & Levassor 20 CV Sport. Compared to a valve-controlled motor from the twenties, the Panhard actually offers the silence of the hammers surprisingly sovereign.
Charles Knight designed the 'valveless' motor
This luxurious advantage of the slide valve Bauart succumbed to a whole series of distinguished brands at the beginning of the 20th century. The British Daimler Company even designed a valve-controlled V12 in 1926. Mercedes, Mors, Voisin, Minerva, Itala, Clément as well as Willys and Stearns had long before relied on the patent of Charles Knight from the USA. As early as 1901, the agricultural machinery specialist designed a so-called 'valveless' engine. In 1907 he assembled an improved version - in an imported Panhard.
Knight had devised a system in which a side mini-crankshaftUsing short connecting rods, both the cylinder liner and an externally running sleeve move against each other parallel to the rotation of the main crankshaft. If the ducts in the upper part of the cylinder and sleeve overlap, fresh and exhaust gases can pass; the combustion chamber is sealed during compression and ignition. The advantage lay not only in the elimination of the noisy, maintenance-required conventional valve control. Slide engines can also cope with bad gasoline, since no red-hot exhaust valve leads to pre-ignition and knocking.
Knight drivers need large cubic capacities
The disadvantage is the speed limit, as more than 4,000 rpm could hardly be achieved until the 1920s. The sliding movements of the cylinder and sleeve also run during the phase of maximum working pressure, so that lubrication problems limit the reliability. Knight drivers need large displacements, as the necessary power is not generated via the speed. The good filling through the large inlet and outlet cross-sections, however, guarantees excellent torque on low tours.
Panhard et Levassor always built engines with conventional valves, but with the Panhard & Levassor 20 CV Sport they still adhered to the slide principle. Noise was already considered improper in the twenties, as soon as it was not made by marching columns, church bells or entertainment venues. And the last Panhard & Levassor 20 CV Sport version, built between 1927 and 1929 in only 76 copies, ultimately wanted to compete with the finest competitors such as a Bugatti T 46 or Hispano-Suiza H6B.
It all started with a factory for woodworking machines
Historically, the Paris-based brand was able to do that anyway. René Panhard and Emile Levassor took over a factory for woodworking machines in 1886. A good friend of Levassor, the lawyer Edouard Sarazin - he had already fought over patent rights for Nikolaus Otto - concludes a license agreement for engine construction with Gottlieb Daimler at the same time. When Sarazin died in 1887, his wife Louise got together with Levassor - as a dowry she brought the Daimler licenses into the later marriage.
Initially, Panhard and Levassor only wanted to build engines from 1889, but soon they turned to complete cars. The first model appeared in 1890, still with a mid-engine, but in 1891 Levassor decided on front-engine and rear-wheel drive - pioneering a principle that was later generally practiced. The new French brand gained renown through racing successes: in 1894 it won, ex aequo with Peugeot, in the first automobile race from Paris to Rouen, and in 1895 in the Paris-Bordeaux-Paris race. In 1896 Panhard et Levassor won Paris -Marseille -Paris. In 1897 Emile Levassor died of the consequences of a racing accident, but the brand survived. The end did not come until 1967, two years after teaming up with Citroën.
DerPanhard & Levassor 20 CV Sport is a mechanical history book
You must excuse my digression. An automobile like the Panhard & Levassor 20 CV Sport with this pedigree is more than just a four-wheeled vehicle. It is a mechanical history book that repeatedly evokes memories of the golden days of the most important means of transport in the 20th century. You can even drive it. All you have to do is get in. But please be careful with your knee. Despite its size, the Panhard & Levassor 20 CV Sport is cut a bit tight at the front. You will remember: Janssen moved the windscreen and A-pillar back ten centimeters for aesthetic reasons.
The double pedal on the far left in the footwell of the Panhard & Levassor 20 CV Sport is used to open the exhaust flap, next to it is the foot switch for the light. The clutch, brake and accelerator are arranged in the usual way. The long lever on the left with the locking button operates the handbrake. The gearshift lever follows an inverted H pattern: the first of the four gears is at the front right. Be glad that the Panhard & Levassor 20 CV Sport does not have the X-schema of other Panhard models in its transmission. Not too much gas; think about the lubrication problems of the gate valves. Then let the clutch of the Panhard & Levassor 20 CV Sport come on, and driving Panhard is so simple: The two-ton truck starts to move comfortably. If the load rolls, the steering forces are bearable; When stationary, the four-spoke wheel of the Panhard & Levassor 20 CV Sport requires so much strength that the inexperienced chauffeur is afraid of bending it. It would be a shame because the Art Deco hub and the similar clips of the spring bars look much nicer in their original geometry.
This Panhard & Levassor 20 CV Sport is unrestored
The gear change in the Panhard & Levassor 20 CV Sport is surprisingly easy and comfortable with a little practice. In need of some fresh air? All you have to do is lift the ring under the side window a little and then pull the disc down on the handle hook. The window is locked by pushing the ring backwards. As soon as this lock is released, the disk floats back up by itself, spring-loaded. Well, almost to the top. Please do not forget that you are driving in an unrestored car built in 1929.
At the Panhard & Levassor 20 CV Sport, the best way to approach intersections is with a certain foresight. Although the Panhard & Levassor 20 CV Sport has four large brake drums on the wheels, only one brake shoe struggles to slow down. He, Panhard, can be brought to a halt. Sometime. Please note the Jaeger speedometer. Its pointer is just jumping from 60 to 65 km /h. Leave it at that for the first test drive. Did you notice how the rigid axles bounced for joy over the short asphalt wave?
Top speed of 160 km /h
No, we are not yet trying out the information in the brochure. Panhard promised 160 km /h for the Panhard & Levassor 20 CV Sport at that time, and test reports are said to be in the company archive in which this hellish speed is actually recorded in 1927. The archive once moved to the former Schlumpf Museum. The old test protocols have not reappeared to this day. The Panhard & Levassor 20 CV Sport is different. In 1976 the Panhard appeared in the garages of the Delage collector André Surmain. Then he retires to the remote corner of a hall in Lyon for the long sleep of 20 years. There it was discovered and bought a year ago by the Swiss classic car specialist Christoph Grohe.
If you want to bring it to a new life, you should first be interested in a special vintage automobile beyond the mainstream - with the characteristics big, rare, heavy and fast. Secondly, he should carry a set of new tires under his arm - in size 17 x 50. These tires are even rarer than a vintage Panhard. Its current owner only managed to get hold of two new specimens, despite a worldwide search. But a Panhard & Levassor 20 CV Sport also needs four. Sorry. Of course you already know that.