Tubular trellis chassis and central engine or sheet metal body and rear overhang engine? This was the eternal technical bone of contention between car designer Mario Colucci and businessman Carlo Abarth, but it would never compromise the professional relationship between the two, founded on sincere, mutual trust.
Designer Mario Colucci came to Abarth in 1958, from Alfa Romeo. The engineer was temporarily transferred to Turin when the two companies signed an agreement to work on creating a new racing car: the Alfa Romeo Abarth 1000. The design would feature innovative technical solutions for Abarth brought by the technician from the Portello plant, in particular the tubular trellis chassis. Unfortunately, the coupé presented on the Bertone stand at the Turin Motor Show remained a prototype but, at the time, Carlo Abarth sensed how useful Colucci’s engineering approach could be for his company. He therefore convinced him to leave Alfa Romeo by promising him an important new role in Abarth, as its technical director.
Abarth and Colucci’s relationship was built on strong mutual respect, despite their differing approaches to the technical aspects of design. Abarth, who was attached to the Porsche set-up, favoured vehicles with a square steel body and rear overhang engine. Instead, Colucci preferred vehicles with a tubular trellis chassis, and the engine in the centre of the car. The reasons behind Abarth’s different vision were also economic: he believed that his solution was cheaper and therefore more profitable for his company.
As a result, two different concepts of the racing car originated in Abarth: one was the vehicle with tubular trellis chassis and engine in the centre, and the other, made of stamped sheet metal, featured a rear overhang engine. The alternating development of both solutions became the leitmotiv of Abarth’s designs throughout the sixties. And even the test drivers, whose opinions were equally as divided, depending on their own personal views, rooted for one of the two solutions, making it impossible to determine which architecture was superior.
The first task Abarth assigned to Colucci, in 1960, was that of designing a Sport Prototype - a lightweight and powerful closed-wheel racing car with a two-seater spider body - in which the engineer could let his creativity run wild. The result was the first Fiat Abarth Sport Spider, with steel tubular trellis chassis and central engine. Engines with different displacements coupled with various gears were tried out in the same chassis, including some made by Fiat and others by French manufacturer Simca, with which Carlo Abarth had ongoing technical and commercial relations.
After a series of ups and downs, the turning point arrived in 1966 with design SE04, for the Fiat Abarth 1000 SP, where 1000 indicated the displacement in cubic centimetres and SP stood for Sport Prototype. Carlo Abarth acknowledged Colucci’s bravura in designing the vehicle using simple and cheap solutions that would make it a manageable option for gentleman drivers, to whom the 1000 SP was mainly targeted.
The new 1000 SP took to the race track with the official Abarth Racing team and the many excellent results it achieved in prestigious races proved to be the best possible advertising means for promoting the vehicle to gentleman drivers
The Sport Prototype was driven by the umpteenth evolution of the Abarth twin-cam engine built on the Fiat 600 base. The unit, located behind the driver, achieved a power output of 105 HP at 8,000 rpm. Considering its displacement of under a litre (982 cm3) the engine would have had a specific power in excess of 100 HP/litre. This value was considerably high for that period in time, also bearing in mind that the 1000 SP was designed to excel both in short uphill races and in long, hard, endurance races.
Its lightweight chassis and body in polyurethane and fibreglass held the 480 kg dry kerb weight of the vehicle, providing a maximum speed of over 220 km/h. Its simple, low, streamlined lines, especially at the front, were possible thanks to the fact that the radiator motor was located on the sides. A solution which, in a very low-lying vehicle, offered better protection for the radiator hoses. This resulted in the typical rounded shape of the rear mudguards, which were preceded by powerful air vents. The vehicle was characterised by a large panoramic glass windscreen, a prerequisite for obtaining homologation as a Sport vehicle in Group 4.
To enable the first specimens of the 1000 SP to race, Abarth had to register the vehicles in the category in which Formula and one-off vehicles competed: the gap between the Abarth proposal and the competition could easily have proved insurmountable, but this was not the case. The first important success was achieved at the gruelling 500 km race on the Nürburgring track, on 4 September 1966: the Abarth 1000 SP, driven by Müller and Steinmetz, won the 1000 category outright and came third overall. The race was won by Ernst Furtmayr - expert uphill racer and winner of the Mountain Championships in Germany and Austria - in an Abarth OT 1300.
The echo of that victory again reverberated just a few days later in Valle d’Aosta: at the Aosta-Pila uphill race, which counted towards the Italian Mountain Championship, Italian driver Leo Cella won the 1000 category, masterfully driving the new Abarth creation to victory. Word of these two surprising successes began to get around and Abarth soon began receiving its first orders for the vehicle. After producing 50 cars, in March 1968, Abarth was able to obtain Group 4 Sport/ Class 1000 homologation.
And the 1000 SP kept on racking up successes, even in the hands of gentleman drivers. Veneto-born driver Lado took home the first victory in the new category, winning the Stallavena-Bosco Chiesanuova uphill race on the roads of his home territory, while other gentleman drivers also contended in the endurance competitions. The Palazzoli/Bottalla and Pasotto/Grano teams won the class at the 1000 Km in Monza on 25 April 1968. Benefiting from numerous developments and transformations, the vehicle continued racing for over a decade, gratifying many gentleman drivers, some of whom would happily wait a long time to receive their vehicles ordered from Abarth.
In this way, Carlo Abarth fulfilled his entrepreneurial goal of selling his customers a trump card, and Colucci experienced the satisfaction of having designed a vehicle according to his own beliefs that also won the favour of his boss. However, their bone of contention regarding the two technical solutions would never be buried. One vehicle that could be considered a Solomonic blend of their two diverging visions was the 1967/68 Abarth 2000 Sport Tipo SE010. Built on a lightweight tubular “Colucci-style” chassis, it was fitted with a rear overhang engine, as favoured by Carlo Abarth. The relationship between the two men would continue to be built on mutual trust and support, and Colucci would continue contributing to the destiny of Abarth with his technical ingenuity for many years to come.