1929 Aston Martin 1.5-Liter

The 1 ½ Litre Aston Martin was in production from 1926 to 1935 under the leadership of engineer Augustus Cesare 'Bert' Bertelli and helped establish a sporting reputation and lasting fame for the marque. They were built in a variety of configurations, states of tune, and wheelbase lengths, with names such as International and Le Mans to capitalize on competition success. With impressive top speeds in excess of 80 mph, they were among the best-handling and best-braking sports cars of their era. Many wore well-proportioned four-seater tourer bodies by A. C. Bertelli, gifted brother of the engineering chief.

The first Aston-Martins, which used a hyphen in its name during this period, were manufactured by Robert Bamford and Lionel Martin. The company's foundation was built on motorsport, and while this brought invaluable publicity, it distracted from the business of manufacturing cars for sale, and thus, approximately 50 examples before the company underwent the first of what would be many changes of ownership.

Early Aston-Martins were powered by four-cylinder side-valve engines, although they did experiment with overhead-camshaft types. The company's single-cam 16-valve motor and its side-valve unit were both the work of S. Robb, previously with Coventry-Simplex. Among the greatest accomplishments of the side-valve Aston Martin was in 1922 when the car - nicknamed 'Rabbit,' and later 'Bunny' - set 25 light-car and 10 outright world speed records at Brooklands.

Built at the firm's new Feltham works, the first 'new generation' Aston Martins came equipped with a new engine designed by Bertelli, featuring overhead camshafts, inclined overhead valves, William Somerville Renwick's patented wedge-shaped combustion chambers, and a displacement size of 1,492cc. It marked the beginning of a long-lived engine design that would continue to power all Aston Martin cars until 1940.

Renwick and Bertelli built a single four-cylinder car with the intent of marketing the new engine to the motor industry at large. However, the allure of designing their own cars was too great, and so Renwick and Bertelli acquired the rights to Aston Martin in 1926. Introduced at the London Motor Show at Olympia in 1927 and initially named the 'Sports Model,' the new model had seating for two, a low pointed tail, and cycle fenders.

The International was first displayed at the 1929 London Motor Show and was based on the team cars of the 1928 season. Built in two wheelbase lengths of 102- and 118-inches, they were produced from 1929 to 1932 with bodies by Enrico Bertelli. Contemporary road tests revealed a top speed of 81 mph, even higher depending on the rear-axle ratio. Changes to this model included brake arrangement and moving the gearbox back to accommodate more foot room.

Aston Martin built approximately 136 cars between 1927 and 1932: 14 on the long chassis and 122 on the short International chassis. The 'Le Mans' label was first applied to the competition version of the (1st Series) International following Aston's class win and 5th place overall in the 1931 Le Mans race.

Models known as the 'Bertelli cars' included the 1½ litre 'T-type,' the 'International,' the 'Le Mans,' and the 'MKII' (and the racing derivative known as the Ulster). The Mark II was introduced in 1934 and was the final Aston Martin to feature the previous model's 1.5-liter, four-cylinder engine, and its ladder-frame chassis was also a development of Aston's original design, but was considerably stiffer due to deeper chassis rails. Nearly all Mark IIs were bodied by Enrico Bertelli at his coachworks next door to the Aston factory in Feltham. Three standard bodies were available, including an open 2/4-seater, a full 4-seater and a fixed-head Sports Saloon. Between 1934 and 1936, approximately 166 examples of the Mark II were built.

During a fourteen-year period, the newly formed Aston Martin Ltd. produced some 617 cars, including 24 Works racing cars that campaigned in national races at Brooklands and Donnington, and at international events such as Ulster TT, Mille Miglia, Targa Abruzzo, Spa, and Le Mans.

Competition
Clinging to its motorsports heritage, examples were prepared to contest the finest international events, including the 24 Hours of Le Mans. In 1928, Bertelli developed the first two of what would ultimately be seven specially-prepared Aston Martin Works racing cars to compete in international races between 1928-1931: LM1 and LM2. The 'LM' prefix distinguished them from their production counterparts. These were lightweight racers that received heavily modified mechanical components, including lightened axles, rear spring shackles, rear spring shackles, bulkheads, and kingpins. Many bronze components were replaced with aluminum, and upgrades were made to the brake shoes and gear ratios. The dry sump lubricated engine was tuned to produce a higher output of 63 horsepower.

In typical fashion for the period, the competition cars were driven (rather than trailered) from the factory to the race track, but during its journey to 'La Sarthe,' the French roads exposed the cars' weakness, with both suffering axle failures. The Bertelli/Eyston car's repaired rear axle failed again during the race, while the Bezzant/Paul car went out with a broken gear lever after 18 hours.

During 1929 and 1930, the works concentrated on domestic races with 'LM3' and 'LM4,' rewarded with a fair measure of success in what had become known as the 'International' model. LM3 made its racing debut at the Double 12 Hours at Brooklands, with driving duties shared by Bertelli and chief mechanic Jack Bezzant. They finished fifth overall and third in the 1.5-liter class. At its next outing at the 1929 Irish Grand Prix, Bezzant and Bertelli finished ninth, followed by the 1929 RAC Tourist Trophy, also in Ireland, where Bezzant failed to finish. Before its next race at the 1930 Double 12 Hours at Brooklands, LM3 was re-bodied with stub-tailed, two-seater Sports Model coachwork. At the 1930 Irish Grand Prix at Phoenix Park, Bertelli and Auburn placed twelfth overall. After serving as a Factory Works development and testing car, LM3 received 'International' 2/4 seater coachwork in 1932 and was sold into private ownership.

The early 1930s were difficult due to the Depression, and Aston Martin was not immune to its effects. Bertelli was forced to seek financial assistance from H. J. Aldington of Frazer Nash, who provided a year's worth of financing and agreed to the building of three new works cars for the 1931 season: 'LM5', 'LM6' and 'LM7', registered as 'HX 4321', 'HX 4322', and 'HX 4323' respectively. The three cars had identical appearances with round drooping tails and narrow doorless bodies. The highly tuned engines produced 70 horsepower and endowed the cars with a top speed of 90 mph.

At their debut race in the Brooklands 'Double 12' event, 'LM6' was driven to a class victory by Bertelli/Harvey, followed by 'LM5' driven by Clive Gallop and Leon Cushman.

The team returned to Le Mans after a three-year absence in 1931 and was met with mixed fortunes. Newsome/Peacock drove 'LM5' but was forced to retire after 125 laps, as did Cook/Bezzant's 'LM7', leaving Bertelli/Harvey's 'LM6' to soldier on alone. They would end the race 5th overall and 1st in class. Later in the year, 'LM5' finished 1st in class and 14th overall at the RAC Tourist Trophy driven by Charles Harvey. Near the close of 1932 or early 1933, LM5 was given 2/4 seater coachwork and sold into private ownership.

The team returned to Le Mans in 1932 and placed 5th and 7th, earning them the Rudge-Whitworth Biennial Cup.

The International achieved many competition successes before being superseded by the Le Mans and Ulster models.

by Daniel Vaughan | Oct 2023