Torrey Canyon – Lotus Ford T86

On March 18th 1967 Shipmaster Pastrengo Rugiati elected to take his charge the 974 ft Torrey Canyon carrying 120,000 tons of crude oil on a disastrous short cut between the Scilly Isles and the Cornish mainland on his way to Milford Haven and ended up causing the worlds largest ship wreck when the boat grounded on the Seven Stones Reef. As the consequent environmental disaster unfolded the ship was bombed sending it 98ft below and the oil spill was repeatedly bombed in a vain effort to keep the oil off the beached of England, France and surrounding islands.

In 1969 Peter Wright was working on the ground breaking BRM P142 which would have introduced aerodynamically induced ground effects to racing car design when John Surtees joined BRM and insisted on opting for a conservative approach and developing the existing BRM P138 and P139 chassis with which Big John scored a season best 3rd place driving the P 139 at the 1969 US Grand Prix before quitting BRM to start his own team.

Peter left BRM and some years later started work for Technocraft to develop a vacuum assisted resin injection composite process which was to be used for the manufacture of body shells for the Lotus Elite, Eclat and Esprit road cars and Colin Chapman’s boat companies.

After the failure of the Lotus 76 in 1975 Colin Chapman asked another ex BRM employee Tony Rudd, now group engineering director at Lotus, to re-think how a Formula One car might be made to make proper use of the front tyres.

Rudd drafted his former colleague Peter Wright in to run the wind tunnel “in his spare time” after his commitments at Technocraft. The fruit of this collaboration was the successful Lotus 78 and world championship winning Lotus 79.

Lotus Ford 86, Goodwood Festival of Speed

The team were not so lucky with the Lotus 80, from which they took a step back with the Lotus 81 before regrouping with their next innovation the twin chassis Lotus 86 seen here.

What Peter had found out was that the Lotus 80 and to a lesser extent the Lotus 81 were suffering from aero flutter causing the cars to porpoise as a result of having springs that were too soft for the aerodynamic loads being put through the wheels and suspension.

By having a twin chassis Peter hoped to use a conventional monocoque chassis in which the driver sat and a separate independently sprung ground effect chassis attached to the first at the outboard ends of the lower suspension. The suspension for the outer ground effect chassis was much stiffer than for the inner monocoque chassis and as a result in theory should not be quite so sensitive to flutter or likely to porpoise.

In order for the car to work not only would the science have to be proven but the rule book scrutinised to ensure the car remained legal. By having the outer ground effect chassis suspended from the bottom suspension links using very stiff rubber bump stops the criteria for having all parts of the car with an aerodynamic influence entirely sprung, was met.

To check the science the team took a 1980 Lotus 81 added a spacer between the engine and the fuel tank through which the central cross member of the outer chassis would pass, made provision for the front cross member of the outer chassis to pass under the driver legs and had had the third rear cross member of the outer chassis pass over the gearbox.

The weight of the outer chassis was kept low using the in house developed carbon fibre process that Peter had been developing for the Lotus road cars and Champman’s boats.

Lotus Ford 86, Goodwood Festival of Speed

Amid much secrecy the Lotus 86 was built and then taken to Jarama for a private test, thanks to the motors heavily revised oil pumps, that were required by the second chassis, a lot of oil was spilled, hence the Torrey Canyon nick name for the car.

Once the leaks had been fixed the Lotus 86 proved that the aerodynamic outer chassis worked providing plenty of down force while the inner monocoque chassis, in which the driver sat, remained free of the porpoising effect that made the car difficult to control.

Upon completion of the test the Lotus 86 which was never subsequently raced was put aside and work started on the Lotus 88 using the same principles.

Thanks for joining me on this “Torry Canyon” edition of “Gettin’ a li’l psycho on tyres” I hope you will join me again tomorrow for a look at an old Rolls Royce. Don’t forget to come back now !

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