Small cars, big ideas
Amilcar dominated voiturette racing during the 1920s with its GP cars in miniature --- but it cost it dear. By Anthony Pritchard
Amilcar — a name redolent of the small sporting cars proliferating in France after WWI. And a name which more than 60 years after the firm's demise still gives rise to speculation about its origin.
Founded in 1921, Amilcar combined the names of its two financial backers Joseph Lamy (who had provided finance for Le Zebre before WWI) and Emile Akar, a grocer by trade. Gabriel Voisin claimed that he suggested the name, but it could also have been a phonetic interpretation of the name of the company president, Emile Akar. In any event, it was a good choice.
Two ex-Le Zebre engineers, Edmond Moyet (chief engineer) and André Morel (in charge of development testing, but with ambitions to be a racing driver) were the driving force behind the company, while Lamy was sales director. They were a successful trio, at least during the 1920s, when the four-cylinder side-valve products of the Amilcar factory at St Denis proved cheap, light, economical, handled nicely and had good sporting looks. But in 1925, Amilcar went a stage further than its rivals by developing a six-cylinder car, one of the very few pure racing cars to enter production before WWII.
Amilcar and Salmson were strong rivals, both in commercial success and driving pleasure, and the battles between them on and off the track were fierce. At St Denis the directors had given Moyet a free hand to plan a new engine that would reaffirm the marque's superiority over Salmson. Moyet's answer was a racing voiturette powered by an engine based on one bank of cylinders of the V12 Delage 2-litre grand prix car which first appeared in 1923.
Work progressed steadily from mid-1924 onwards. The first two cars were typed the CO (an abbreviation of course), the engine of 1098cc (55x77rnm) with one-piece cast-iron block and integral cylinder head. The crankshaft ran in seven main bearings, with rollers for the inner bearings and ball-races for the ends. The twin overhead camshafts were driven by spur gears at the front of the engine and operated two valves per cylinder; oil was fed to the valve-gear through the hollow camshafts. Ignition was by magneto and there was dry-sump lubrication.
Originally, the CO was not blown, but in 1926 a Roots-type supercharger was fitted. Mounted at the front of the engine, this compressed at a hefty 17psi and was lubricated from a separate oil tank. A Solex carburettor was used. Power output unsupercharged was around 75bhp at 6500rpm, and 90bhp at 5600rpm after the blower had been added. Transmission was by a single-plate clutch and four-speed gearbox. The chassis was similar to that of the four-cylinder CGS model, with front suspension by semi-elliptic front springs and quarter-empties at the rear. The body was a very neat, pointed-tail two-seater in unpainted aluminium alloy.
Early races of the works cars
After Morel had extensively tested the first car at the new Montlhéry `autodrome', he drove it at Gaillon hillclimb in October 1925. Apart from winning his class, 12mph up on the previous record, he finished third overall behind René Thomas (Delage) and Jean Chassagne (1.5-litre Darracq). In '26, the new Amilcar team, consisting of Morel, Charles Martin and Arthur Duray (replaced in '28 by Jules Moriceau), proved the sensation of voiturette racing and was almost invincible.
The season started in February with La Turbie hilklimb: Morel won his class. A month later two cars were entered in the voiturette class of the Provence Grand Prix: Martin retired, but Morel won the class from a Salmson. In May, Morel and Moriceau, sharing a car, broke three class world records at Arpajon, including the flying km at 123.21mph. Morel and Martin drove the usual cars in the French Voiturette Grand Prix at Montlhéry, but Duray had the new CO, with a 3in shorter wheelbase of 7ft lin and more rigid construction. There were only one or two of these cars and the three team members drove it (or them) at different races in 1926-27. Although the Amilcars dominated the early laps of the 87-mile Montlhéry race, all three retired with valve spring failure.
After a number of successes in minor events, Amilcar ran in the 249-mile Italian Voiturette Grand Prix at Monza on September 5. In another display of St Denis superiority, Morel (who averaged 82.60mph) and Duray took the first two places ahead of de Joncy (BNC); Martin retired because of supercharger failure. The works team then made a sensational UK debut in the JCC 200-Mile race at Brooklands on September 25, when Martin won the 1100cc class at 66.65mph, followed across the line by team-mates Duray and Morel. In October, Duray won at Montlhéry, while Morel set a new course record in the 17 Tournants hillclimb and again won his class at Gaillon.
During 1926, Moyet had worked on the CO monoplace `experimentale', a narrow streamlined single-seater with no brakes at the front and much reduced weight. The driver straddled the propshaft and the gear lever was between his legs. Morel tested this car at Montlhéry, found it so bad that he, apparently, would not even talk about and it was dismantled so that the components could be used again. There is no known photograph of this car.
The works cars in 1927-29
Following the relaxation in the regulations requiring racing cars to have two-seater bodywork, Moyet developed the CO déporté for 1927. This was an offset single-seater with a shorter stroke 56x74mm (1094cc) engine, with the supercharger mounted horizontally to cure a tendency to flood. Claimed maximum power in this form was 105bhp at 6500rpm (subsequently increased in '28 to 107bhp at 6700rpm). The chassis was narrower, lower and stronger. Amilcar built only three of this model, two with traditional radiators and one with a cowl.
During 1927, Amilcar continued to notch up a large number of successes. The first appearance of the CO déporté was in May in a speed trial at Bordeaux, where with this car and a CO Morel took first and second places in his class. In July, Martin won his class in the 430-mile San Sebastian GP, but Morel retired because of wheel bearing failure. Other successes were wins by Duray in the Voiturette GP at Montlhéry and in the 1100cc category of the Boulogne Light Car and Voiturette GP. In the JCC 200Mile race at Brooldands in October, Morel won the 1100cc class and came second overall to Malcolm Campbell's Bugatti ; Vernon Balls, who had sponsored the entry and been loaned a works car, was third; Martin made it a 1-2-3.
Amilcar scored another string of wins in 1928. One of the CO déporté cars was fitted with a 1270cc engine said to give 118bhp at 6700rpm. The cars now ran in both the 1100 and 1500cc classes --- and frequently won both. There were fewer voiturette races this year and many of Amilcar's successes came in sprints and hillclimbs, but Moriceau finished fourth overall (first in class) in the Grand Prix d'Antibes in April and won his class in the Rome Grand Prix.
St Denis had also been developing the MCO record cars (also known as the MCO déportés ), which appeared in 1928 in both 1100 and 1270cc forms. Offset single-seater bodywork was retained, but they had a wheelbase shortened to just under 7ft, they were narrower, lower and substantially lighter than previous cars, and had a streamlined body with headrest and discs over the wire-spoked wheels (sometimes at the front only).
The 1100cc car ran in sprints at Arpajon, Montlhéry and Geneva, while Morel won a number of events with the 1270cc car in July. Amilcar could no longer afford a works racing programme and the competition department closed early in 1929. Moriceau entered a 1270cc car privately at Indianapolis that year, and qualified faster than five cars with 1500 engines, the maximum allowed; he retired after he spun off on lap 31 and damaged the steering.
The production cars
The six-cylinder car was such a success that amateur drivers pressed Amilcar to sell them one. Moyet put in hand work on a suitable version, designated C6 (C for client). The chassis was a shorter but wider version of the CO court, the cylinder dimensions were the revised 56x74mm, the head was detachable and there were smaller valves. On a reduced boost of 8.4psi the claimed output was 62bhp at 5600rpm. After a C6 chassis had been shown at the 1926 Paris Salon, a car was tested at Montlhéry and production examples became available in mid-1927. The C6 was sold only as the two-seater Supersport with cutaway cockpit sides, and cost 60,000FF, more expensive than a Bugatti Type 37. By 1930, the price had risen to 80,000FF, and the last example was sold in '31.
The majority were sold in France and the best-known buyer was José Scaron, the Amilcar agent in Le Havre, who achieved many successes from 1928 until '33. Vernon Balls, the UK agent, imported seven C6s and raced one himself; other examples were sold in Belgium, Italy, Sweden, Germany and Switzerland. British owners of C6s did well at Brooklands and similar venues.
One of the outstanding performers was W E Humphreys who had his black-painted car prepared and modified by Alec Francis. He fitted special camshafts, six separate water take-off pipes rising from the cylinder above each bore to cure overheating round the valves, and a special Amherst Villiers supercharger compressing at 16psi. With the C6 in this form, Humphreys lapped at 105.97mph in a short handicap race in 1931 and was leading the 1100cc class of that year's 500-Mile race when the front axle broke three laps from the finish. Henken Widengren had his car fitted with an offset single-seater streamlined body with along, pointed tail. He took it to Montlhéry in '33 and broke the 1100cc hour record at a speed of 115.54mph.
Amilcar reached its peak with the six-cylinder racing cars --- and then it was downhill all the way. The company survived the 1920s on the continuing --- albeit waning --- demand for its four-cylinder cars and the prestige of the racing voiturettes. The firm gradually moved over to the production of touring cars with four-cylinder and straight-eight engines, adopting a Delahaye engine for one model in '34, and was taken over by Hotchkiss in '37.
The last Amilcar was the Compound, with front-wheel drive under Grégoire patents. Announced in 1938, the Compound featured unit construction in Alpax aluminium alloy, independent suspension front and rear, a 1185cc side-valve engine, a four-speed gearbox mounted in front of the engine and cable linkage to a gearchange mounted on the dashboard. It was a hotchpotch of the advanced and the abysmal. Production did not get under way until '39 and fewer than 700 had been built when WWII halted production. It also brought an end to Amilcar, although Hotchkiss survived until '55 and an improved Compound was revived by Imperia in Belgium in early post-war days.
Bernard Harding's C6
Total Amilcar six-cylinder production amounted to close on 40 cars, of which something under half survive worldwide. Two of the most interesting were the cars raced by Humphreys and Clayton (the later was so extensively modified that it became known as the 'Clayton-Amilcar). Both were acquired by Owen Finch immediately after WWII. They were frequently raced and modified by him and parts were exchanged between the two. In 1961, Bernard Harding acquired one of these cars, which has the chassis of the Humphreys car but many parts from the Clayton car. Subsequently, he obtained the log book of the Clayton car and adopted its original registration number, YV 91.
Bernard rebuilt the car, and he has recently rebuilt it for a second time. An Amilcar C6 must be one of the few historic racing cars which can be driven on the road. The method of starting a car of this type was common for the period, but is very complicated by today's standards --- the procedure is set out on p83. There is, of course, a central throttle. When you are satisfied that the car is fully warmed up, then the ignition is fully advanced and away you go. For road use, this Amilcar is fitted with a fishtail silencer, but still remains noisy, barking under acceleration and roaring as speed builds up. Stopping power is excellent thanks to hydraulic brakes with Alfin ex-Aston Martin DB2 drums; the ride is firm on its Hartford dampers, but not uncomfortable. Hold-ups necessitate retarding the ignition to prevent the engine from stalling. It is a long time since anyone took performance figures for these now near-70-year-old cars, but the acceleration is fierce, and on ordinary main roads the C6 cruises happily at around the legal limits with plenty more to come. Don't complain about the lack of originality of Bernard's car; there's no such animal as an original C6. As chassis numbers were on a plate attached to the body and usually have been lost through carelessness or convenience, it is by major modifications that individual C6s can be identified.
Starting the C6 Amilcar
* Turn on the oil tap situated between the oil tank and the main oil pump
* Make sure that the fuel tank vent is closed
* Use the hand air-pump to produce a pressure in the fuel tank of about 1.5psi
* Turn on the main fuel tap
* Check the gauge for pressure in the carburettor
* Turn on the tap that permits fuel to reach the Ki-gas starter system
* Unscrew the Ki-gas pump from the locked position
* Turn on the electrical master switch
* If the engine is cold, give three pumps from the Ki-gas system
* Turn on the ignition
* Make sure that the ignition is retarded
* Press the starter button
* After a few pops and bangs, the engine will settle down and run smoothly
(NB Originally no self-starter was fitted to these cars --- they were started on the handle)