Although the Formula governing GP racing was much the same to the end of 1960 as it had been for the preceeding four years, the FIA now stipulated that the racing engines must function on petrol, at once dispensing with the artificial cooling effect of alcohol fuels. The mixtures used had provided engine reliability for those who were prepared to put large quantities of fuel of this 'forgiving' nature in the tanks of their cars before the start of a race and at the refuelling stops. Ferrari had the happy advantage of their Formula Two engines already being petrol burners, and now enlarged them into proper Grand Prix Formula cars. Maserati, however, withdrew from racing as a consequence of the changed ruling, even though the definition of petrol was stretched to mean 'AvGas' aviation spirit, of 130 octane rating.
Vanwall and BRM were also very hard hit by the change. The Vanwall had relied on extreme nitro-methane mixtures to produce its claimed 290 bhp, as installed in the car, and this engine would lose nearly 30 bhp if run on petrol; their fuel-injection system had to be drastically retuned for straight petrol fuels to release even that much horsepower. The four-cylinder BRM engine, with its stroke/bore ratio of 0.73 : 1, while giving an effective piston area figure and very high rates of rotation, was very dependent on cooling from alcohol for its internals. Particularly prone to overheating were its valves, of which the inlet valves were much larger than normal and the exhaust valves were of more usual size.
The Ferrari, now called the Type Dino 246, its 65-degree, V6-cylinder, engine being of 85 x 71 mm (2417cc), was good for 9400rpm according to some authorities and probably gave 280 bhp in its 1958 guise. Lotus now came onto the scene, with Formula Two-type cars, powered by the 'stretched' Coventry Climax engine. At first of only 2-liter and 2.2-liter capacity, these new Lotus cars were not only extremely light but they had suspension refinements that were the first of the great Colin Chapman innovations that have become the hallmark of the Lotus stable down the years.
The BRMs were heavier but had been developed into effective racing cars with good torque characteristics; liked by most drivers. The rear-engined Coopers were on the way to absolute success and by 1959 had double wishbone independent suspension at the back, still in conjunction with a transverse leaf spring. Although tire sizes were generally increasing, BRM changed from 16 in to 15 in diameter covers. Dunlop were rapidly ousting all opposition as leaders on racing-tyre techniques, with the new R5 racing tire , which was finding favour with several teams.
Aston Martin entered FI racing with the too heavy DBR4/250, developed from the better known Type DBR/300 sports-car, but of old-fashioned chassis conception, for all its close resemblance to a Maserati 250F. Maserati, in fact, had been in the ascendant up to their retirement from racing, having carried Fangio to his fourth successive World Championship. This was a triumph for the conventional well constructed, sensibly developed product of a factory well versed in racing, and employing the top drivers. Although there was far more to winning a 1959 motor race than absolute power, it must be remembered that whereas the Dino V6 Ferrari was pushing out a useful 290 bhp at this time, the Coventry Climax, although its fire-pump power unit background had been transcended, was only good for about 240 bhp, at the most.
Yet by the close of the 1959 racing season the rear-engined genre had made it, very definitely, over the front-engined cars, whose now superseded layout had dated back to the Panhard-Levassor conception of 1895. All manner of things had emerged during this 1958-1960 Formula. Vanwall had gone back to normal racing bodywork, but Connaught had come up with their semi-faired-in creation, nicknamed the 'toothpaste tube', and Porsche had brought out a single-seater RSK. To their credit, BRM had an early attempt at building a rear-engined car, although at the beginning of the 1960 season their old front-engined models were the ones which they raced. Lotus had been defeated in 1959 by poor roadholding qualities, so Colin Chapman started again, with a clean sheet of drawing paper.
The result was the Lotus 18, which had the notably light weight of 980lb (empty) and also boasted an impressively low frontal area. Behind the driver, in an almost genuine space-frame of multi-tubular type, there lived the Coventry Climax FPF engine, while fuel, oil and water were accommodated in the nose of the Lotus, which was of a mere 9 square feet frontal area. Low roll centre rear springing was a very deliberate aspect of the new car, but Chapman retained the magnesium- alloy disc wheels, of the shape that had distinguished his Type 16 Lotus from other contemporary racing cars.
The lesson was that by putting the engine behind the driver it was possible, in a short, compact car, to save weight and reduce frontal area, and therefore wind drag. Chapman had only 240 bhp to play with, but from an engine weighing but 290 lb, which can be compared to the 450 lb of earlier GP engines. In this context, the rear-engined BRM was r oo lb below the avoirdupois of its earlier front-engined ancestors and also had nearly two square feet less body- work area exposed to frontal drag. So Cooper with the benefit of experience were on a very good wicket, especially after they had introduced coil-spring rear suspension and gone over to five-speed gearboxes. Ferrari had also turned to the use of a Dino 246 motor, behind the driver, in his factory cars.
It was the Scarab, sponsored by Lance Reventlow, which was now looking old-fashioned, although just introduced to the European Grand Prix scene; the car had a front-located engine, a Chevrolet gearbox, and was of heavy conception, with a very upright driving position. Its saving grace was that it made up in beautiful finish what it lacked technically. So the 2½-liter years ran out, characterised by the emergence of the new theory that the engine should be placed behind the driver to gain a compact body form. The BRMs of this kind were steadily improving, and the day of the Lotus was obviously soon to dawn, being held back for the moment by obscure carburation maladies that for some peculiar reason did not trouble the Coopers.
Both Lotus and Cooper were of less weight and could therefore out-strip the BRM on acceleration. This led to a new version of BRM with some 60lb in weight lopped off it and with double-wishbone rear springing, which Vanwall had also adopted. Although the so-called European Grand Prix of 1960, run at Monza, was won by a front-engined Ferrari, the day of the conventional racing car in this sphere was over. Thus came the beginnings of the change that was to render a road-racing motor car, the highest form the racing automobile could take, something quite different from the cars used for business and pleasure by the ordinary citizen.
As the years advanced, the gulf widened. There was also the fact that much importance was being placed on the new Drivers' World Championship, which drew public interest more to the drivers than to the technical quality and performance of the racing cars., This was the commencement of the 'circus' aspect which has engulfed modern Grand Prix motor racing. By 1960, the Driver's World Championship had run for a decade. It had seen Farina, Fangio (five times), Ascari (twice), Hawthorn and Jack Brabham (twice) in the seat of honour, these aces relying on Alfa Romeo (twice), Ferrari (three times), Mercedes and Maserati, Mercedes alone, Maserati alone, Lancia-Ferrari and Cooper (twice). It is significant that it was Brabham who took the crown in the last two years of the 2½-liter Formula, with Cooper cars, and that it was he who had pioneered the rear-engined conception of Grand Prix racing car, which was soon to dominate the sport.
Phil Hill of the United States was World Champion in 1961, Graham Hill in 1962 and 1968, Jim Clark in 1963 and 1965, John Surtees in 1964, Jack Brabham in 1966, Denny Hulme in 1967, Jackie Stewart in 1969, 1971 and 1973, Jochen Rindt in 1970, Emerson Fittpaldi in 1972 and 1974, Niki Lauda in 1975 and 1977, James Hunt in 1976, and Mario Andretti in 1978. Sadly, the 1970 World Championship was decided posthumously. Rindt was killed practising for the penultimate round, yet by the end of the year no one had overtaken his points-total so the FIA declared him champion.