How the Lotus 72 drove a wedge between the field

A key concept allowed the Lotus 72 to flourish for years to come

Jochen Rindt at the 1970 F1 British Grand Prix at Brands Hatch

DPPI

display_e35f2226d3

Given the extent of its innovation, the Lotus 72 should have had a bigger advantage in 1970. Although Jochen Rindt won four races in a row, it was only dominant at Zandvoort. In France, it was boosted by the retirement of Jacky Ickx’s Ferrari and the puncture of Jean-Pierre Beltoise’s Matra ahead of it. The Lotus was pushed hard by Chris Amon’s basic March. At Brands, it was set to be beaten by Jack Brabham, and although Rindt was in control at Hockenheim, he was pushed by Ickx. None of the other cars had the space-age tech of the 72. It was a reflection of its early development, as it would still win races in its fifth season.

Colin Chapman had planned a back to core principles design, and Maurice Philippe carried out the brief. Tyre design progress in the ’60s drove Chapman’s vision. Advances had made lower aspect ratios feasible, and the tyres had become fatter, so existing cars such as the Lotus 49 were unable to take advantage of the greater potential traction of the rear tyres. Chapman sought a more rearward weight distribution. “Four-wheel drive had been Colin’s original way of achieving this,” said Lotus competition manager Dick Scammell in 2013. “But that brought four-wheel- drive problems. The 72 was the two-wheel-drive solution to the traction problem.”

From the archive

That drove the key feature of the car: moving the radiators from the conventional nose position to the sides. Aero and mechanical gains followed. The 72 had 65 per cent of its weight on the rear axle. Conventional front-rad cars had no more than 60 per cent. With no radiators to house, the nose could be made a wedge, Lotus had found gains from the design in its 56 Indycar. Modern CFD proves the 72’s nose created ground effect.

With no radiators up front, there was space to bring the brakes inboard, improving aero and reducing the unsprung mass. The lighter load on the front axle meant Firestone could develop a special two-ply front tyre. Softer compounds could be used, without overheating. Once the ill-conceived anti-dive and anti-squat geometry was removed from the suspension, the 72 was ready to win.

Comments

Loading Comments