By 1932, Bertelli had considerable experience racing his Aston Martins, and was indeed one of the very few designer/manufacturers who regularly drove his own cars in national and international events.
This gave him considerable insight into the future design and development of his competition cars and lessons learned from racing the ‘International’ was immediately put to good use with the new second series works team cars.
Using the new chassis and with the ‘Competition 2 Seater’ as the prototype, three new low radiator pointed tail cars were built, incorporating all the modifications to chassis, brakes, transmission and engine that had been made to date.
Amongst these changes was the greatly improved cylinder head with a well designed and relatively efficient inlet manifold with 1⅜" side draught carburetors and four branch exhaust manifold, similar to the last three ‘International’ team cars. New camshafts were continually being developed in the racing department and tested in engines on its own dynamometer. Still dry sump, and with lightweight timing gears and shafts, this attention to detail even extending to the Aston Martin designed gearbox where the gears were drilled for lightness and the cases were made of electron instead of aluminium. Special attention was paid to the gearbox ratios, with the wheel size now 18".
LM8, 9 and 10 were built in the racing department in eight weeks and ready for a trial run at the ‘Brooklands 1000 Mile Race’, a fortnight before Le Mans. It quickly transpired that the front springs did not work at all well, producing difficult handling characteristics and the three cars were quietly withdrawn. After modification, the entry at Le Mans saw two of the cars finish, the highest placed, Bertelli in LM8 crossing the line in seventh place winner of the Rudge Cup. Sadly, due to financial constraints the three team cars were sold off soon after Le Mans, with LM8 now fitted with a 2/4 seater body.
So, for the 1933 Le Mans entry, LM7 was bought back into service with Mort Goodall driving, the owner of LM9 was persuaded to lend the works his car and LM10 was bought back by the works., It was by now highly drilled, in an attempt to lighten it as much as possible (for the 1933 500 mile race at Brooklands), and had transverse front shock absorbers, later to be seen as standard on the third series cars, the ‘Mark II’. Both LM9 and 10 had various engine upgrades (mostly cam and rocker ‘top end’ changes) with the more powerful of the two engines fitted to the heavier car, LM9. The design of the wing stays was yet again a Bertelli obsession, with the wings secured by stays and cables. During the race, the wings on LM10 having come loose yet again, were reinforced by lengths of washing line that mysteriously appeared at the side of the circuit! Unfortunately LM7, now with two years hard racing and rallying behind it retired with a rod through the side of the block, but LM9 came in fifth overall and first in class and LM10 seventh and second in class, second and fourth in the Rudge Whitworth Cup respectively.
Specification
The second series team cars are similar to the ‘Competition 2 Seater’ in terms of chassis running gear and brakes. All components were lightened as much as possible and Electron was used for all castings where aluminium would normally have been used.
Engine specification varied from car to car and race to race, but the second series cylinder block was used with the ‘Le Mans’ cylinder head in combination with 1⅜" carburetors and uprated high lift camshaft. The exhaust was the four branch system first seen on the first series team cars with gasses running through a ‘Brooklands’ box. Timing gears, gearbox gears and shafts were all lightened by drilling and boring respectively. Triple valve springs and threaded valve collars and caps were used in 1932 with stronger rocker fingers for the 1933 season.
A variety of crown wheel and pinion ratios were used, depending on the length of the circuit and the power of the engine but 4.66:1 would probably have been the norm.
Gearboxes were very close ratio with different constant mesh gears employed to lengthen or shorten first gear.
The doorless pointed tail coachwork was particularly lightweight and was fitted with a single aero screen and full width mesh screen. The rather flattened wings were attached by stays to the chassis and braced with cables rather than the brake back plates. Hence, there was greater gap between the wings and the wheels than when attached to the back plates. This system was not reliable and Bertelli famously resorted to using rope to keep them attached to the car during the 1932 Le Mans 24 Hours Race. Full length undertrays were fitted and the larger oil tanks seen on the 1931 team cars were retained. The spare wheel was fitted in a frame over the fuel tank and rear axle with the double eared turn bar for the central fixing protruding through the bodywork just ahead of the two fuel filler caps.
LM10 was subsequently considerably lightened, including the handbrake, which was drilled its entire length. It was also fitted with an experimental pair of transverse shock absorbers, the prototype for the 1934-35 third series Mark II.