Here’s Part 4 of our theoretical look at the comparative speeds of leading GP cars: mid-engines, monocoques and wings arrive
Words Mark Hughes. Photography: LAT
1959 Cooper T51
Index figure: 172.9
Virtual lap time of the current Spa circuit: 2m 48.1s
The car that made the mid-engined format stick permanently. The pre-war Auto-Unions had thwarted one of the key advantages of the layout by adopting very long engines. Not so the four-cylinder Climax-powered Cooper. The format enabled the car to be lighter and lower, centralised its mass for better direction change and gave it better traction. Its chassis and suspension were not geometrically great; the car was often on three wheels, with the outer front tyre supporting 100 per cent of the front cornering load.
1960 Lotus 18
Index figure: 177
Virtual lap time of the current Spa circuit: 2m 43.9s
Colin Chapman was forced to follow Cooper’s mid-engined lead. But he applied more science to the job, with a better triangulated arrangement of chassis tubes and a suspension geometry that minimised lateral weight transfer during cornering, thus keeping more of the front rubber on the road for more of the time and taking some of the load away from the more stressed outer tyre. It was extremely light – at 390kg it’s the lightest GP-winning car and its apparent frailty was a cause of some concern to the governing body. A 450kg minimum weight was imposed the following season.
1961 Ferrari 156
Index figure: 170.5
Virtual lap time of the current Spa circuit: 2m 50.6s
A drastic reduction in engine size – 1.5 litres normally aspirated – took lap times back to 1958. It also did Ferrari a great big favour; its British rivals didn’t have a readily available competitive motor whereas Enzo had been building F2 1.5-litre V6s for some years. For his first serious attempt at a mid-engined car, he installed Carlo Chiti’s latest V6 in a chassis that was more Cooper technology than Lotus, then clothed it with a beautiful Fantuzzi body. So was borne the ‘sharknose’, the last frontline GP car with wire wheels.
1962 Lotus 25
Index figure: 175.5
Virtual lap time of the current Spa circuit: 2m 45.4s
With the 25, Chapman applied the Jaguar D-type’s monocoque technology to an F1 car. The 25’s tub was three times as stiff and half the weight of the 24’s tubular chassis. With a drag-reducing ‘lie-down’ driving position, it was as low-drag as an open wheeler could conceivably be.
1963 Lotus 25
Index figure: 178.4
Virtual lap time of the current Spa circuit: 2m 42.4s
The first of the 1.5-litre cars to better the lap-time performance of the best of the 2.5s from just three years before. It was only lightly modified from ’62 and most of the lap time improvement came from Dunlop.
1964 Lotus 25
Index figure: 179.7
Virtual lap time of the current Spa circuit: 2m 41.1s
Modified to accept the change from 15-inch to 13-inch diameter Dunlops and with another 12bhp through the season from Climax. Otherwise much as in ’62. \
1965 Lotus 33
Index figure: 183.1
Virtual lap time of the current Spa circuit: 2m 37.6s
Essentially a 25 with a lighter, simpler monocoque. Dunlop and Goodyear rivalry produced big lap time improvements.
1966 Ferrari 312
Index figure 188.9
Virtual lap time of the current Spa circuit: 2m 31.5s
This was marginally the fastest of the cobbled-together 3-litre cars. It made do with an updated version of the old Colombo sportscar V12, defining the car as big and heavy.
1967 Lotus 49
Index figure 196.6
Virtual lap time of the current Spa circuit: 2m 23.6s
The staggering leap in technology this car represented can be gauged by the fact that it achieved a greater lap time reduction than did the previous year’s doubling of engine capacity. Using the engine as a stressed, structural part of the chassis wasn’t new – it had been a feature of the ’54 Lancia D50 as well as the ’66 BRM and Lotus 43. But the 49’s Cosworth DFV engine was designed by Keith Duckworth with the feature in mind. The Ford-funded 90-deg V8 was at the heart of the technology leap, its compact dimensions making everything else look prehistoric.
1968 Ferrari 312/68
Index figure: 199.5
Virtual lap time of the current Spa circuit: 2m 20.5s
Its chassis and suspension endowed it with a near-perfect balance, allowing Chris Amon to express his considerable talent. In pre-wing form, it was definitely a better-handling car than the Lotus 49. During Friday practice at Spa it became the first F1 car to feature a full rear wing.
1969 Lotus 49B
Index figure: 202.9
Virtual lap time of the current Spa circuit: 2m 17.0s
The B version of the 49 had been introduced at Monaco ’68. Distinguished by new, wedgier bodywork, a longer wheelbase and Hewland transmission, it responded well to the huge suspension-mounted wings. The double failure of these wings at Montjuich ensured they were clipped thereafter.
1970 Ferrari 312B
Index figure: 208.1
Virtual lap time of the current Spa circuit: 2m 11.6s
A Forghieri masterpiece, the heart of which was his new 180deg ‘flat-12’ which brought the centre of gravity to five centimetres lower than a DFV installation and gave it an initial 25bhp advantage. The beautiful body hid a monocoque/spaceframe mix and the chassis had a great balance.
1971 Tyrrell 001-3
Index figure: 209.4
Virtual lap time of the current Spa circuit: 2m 10.3s
Derek Gardner’s first attempt at an F1 car was for Ken Tyrrell’s new marque and showed a distinct Matra influence; similar suspension and side fuel tanks that ballooned out near the bottom to keep the c of g low. A full-width nose scooped as much airflow as possible over the front wheels.