1958 AC Ace-Bristol Roadster
Chassis no. BEX 421
Engine no. 100D 779

"Of them all, the Ace was the truest sports car: it could be used for daily commuting or for high-speed long-distance touring, but it could also be driven to a race meeting, campaigned with distinction, and driven home again - even if that race was the Le Mans 24 Hours." - AC Heritage, Simon Taylor & Peter Burn.
The success of Cliff Davis's Tojeiro sports racer prompted AC Cars to put the design into production in 1954 as the Ace. The Davis car's pretty Ferrari 166-inspired barchetta bodywork was retained, as was John Tojeiro's twin-tube ladder frame chassis and Cooper-influenced all-independent suspension, but the power unit was AC's own venerable, 2-litre, long-stroke six. This single-overhead-camshaft engine originated in 1919 and with a modest 80bhp (later 100bhp) on tap, endowed the Ace with respectable, if not outstanding, performance.
In 1955 AC added a hardtop version - the fastback-styled Aceca - and from 1956 onwards both models became available with the more powerful Bristol 2-litre, six-cylinder engine with its ingeniously arranged, pushrod-operated inclined valves. Although taller and heavier than AC's own engine, the BMW-based Bristol was considerably more powerful thanks to its superior cylinder head design and down-draught carburettors. Up to 130bhp was available from the Bristol unit in road trim, in which form the Ace could touch 120mph (195km/h), while around 150bhp could be wrung from it for racing.
In 1955 AC added a hardtop version - the fastback-styled Aceca - and both models became available from '56 with the more-powerful (up to 130bhp) Bristol six-cylinder engine. The l,971cc Bristol six was based on that of the pre-war BMW 328, which featured an ingenious cylinder head, designed by Rudolf Schleicher, incorporating hemispherical combustion chambers and inclined valves without recourse to overhead, or twin, camshafts. Instead, the earlier BMW Type 319 engine's single block-mounted camshaft and pushrod valve actuation were retained, thus avoiding an expensive redesign. Two rocker shafts were employed, one situated above each bank of valves, giving the engine an external appearance almost indistinguishable from that of a twin-overhead-cam design. Downdraft inlet ports contributed to the motor's deep breathing, and its tune-ability made it a popular choice for British racing car constructors, most notably Cooper, during the 1950s. Externally, Bristol's clone of the BMW motor differed little from the German original, the most obvious difference being the adoption of SU, rather than Solex, carburettors part way through production. The most significant changes made by the Bristol designers were metallurgical, their utilisation of the highest quality materials contributing to greatly increased engine life.
The Bristol-engined Ace was not only more powerful, it was also considerably more expensive, costing £2,011 in 1957, an increase of 22% over the price of the AC-engined version. For that you could buy two MGAs, and even Jaguar's XK140 was cheaper than the Ace Bristol. Nevertheless, by the time Ace production ceased in 1963, more than half the 723 cars built had left the factory fitted with Bristol engines.
The combination of a fine-handling chassis and a decent power-to-weight ratio helped the Ace to numerous successes in production sports car racing; arguably its finest achievement being a 1st-in-class and 7th overall finish at Le Mans in 1959. Indeed, its basic soundness and versatility were reflected in the fact that relatively few major changes were found necessary when the Ace was endowed with Ford V8 power to create the legendary Cobra.
Towards the end of production the Ace was made available with the 2.6-litre overhead-valve Ford Zephyr engine installed. The first cars were converted by Ken Rudd of Ruddspeed before the factory took over. A 12-port aluminium-alloy cylinder head, developed by Raymond Mays of ERA and BRM fame, was usually fitted together with other internal modifications, in which form the Zephyr-derived unit produced 155bhp on triple SU carburettors and up to 170 horsepower on triple Webers. Only 36 examples of the Ford-powered Ace 2.6 were made, making it by far the rarest of the three engine types offered.
Leaving the factory on 1st May 1958, this left-hand drive Bristol-engined Ace was delivered new to Ets Chardonnet in Paris, France and registered to its first owner, Jean Balaresque, on 14th May 1958. The original colour scheme was light blue metallic paintwork with red interior trim and beige hood.
Mr Balaresque kept the Ace until March 1963 when ownership passed to Boutkil Abdelhouhab in Paris. During Mr Abdelhouhab's ownership the Ace was involved in an accident in Italy, damaging the front of the body. Garage de Lorraine then rebuilt the AC in March 1964 via Carrosserie Delvalet using the slightly different front end of the Zephyr-engined model it wears to this day. Garage de Lorraine sold the Ace later that year to next owner Nicolas Gilles. The car then had a further four known owners (including Gilles for a second time) before being acquired on 20th April 1995 via Christophe Pund by the current vendor, founding member of the AC Club de France, Alain Mauboussin, of the eponymous jewellery manufacturer, Place Vendôme, Paris.
Over the last 27 years the enthusiast vendor has participated in numerous rallies with the Ace including five Coupes des Alpes; three Tours Auto; all the AC Club France rallies; ACF Rallies; Transalpina Rallies; and other rallies in Belgium: Z Trophy, HVCB, etc. One of the most memorable was the Louis Vuitton China Run Classic from Dalian to Beijing in May 1998, at a time when there were no hotels or gas stations (a tanker truck followed the competitors and the accompanying 50 journalists).
A copy of this very well documented car's history, prepared by Bertrand Leseur, AC Club France registrar, is on file together with a complete dossier of photographs of its restoration, which was carried out by J C de Penfentenyo during the late 1980s. There are also many bills in the file dating back to 1989. Now fitted with a BMW five-speed gearbox, the car was repainted metallic green and then light blue metallic in 2006. In 2003 'BEX 421' was the subject of an article by José Rosinski well known automotive journalist and racing driver in Auto Rétro (September edition).
Presented in beautiful condition, 'BEX 421' represents an exciting opportunity to acquire the most sought after Bristol-engined version of this classic British sports car, eligible for numerous historic events.