SPEED RECORD

Hokitika Guardian, 20 March 1930, Page 6

SPEED RECORD

KAYE DON’S EFFORT

(The Special Tyres.)

The 4,000-h.p. Sunbeam car, Silver Bullet, with which Mr Kaye Don will attempt to heat the world s land speed record, at Daytona, Florida, United States, is the most wonderful mot or-car in the world, and naturally it could not be run on the road, so the hack wheels were removed and each axle was coupled to huge brakes.

Air Louis Coatalen. the designer, was present with Mr Kaye Don and officials of the Sunbeam Company.

Mr Coatalen raised his finger, there was a hiss of compressed air, and suddenly almost effortlessly both engines broke into life. At the bidding of the engineer, who stood at the contiolboard. they were opened up, the whole shed was filled with the deep-throated roar from the exhaust of the 24 cyclinders, and the whole factory seemed to shake.

At one end of the car a controlhoard, showed temperatures and oil pressures while two throttle levers controlled the engines.

One of the most important factors in connection with the forthcoming attempt on the world’s speed record by Kaye Don the English racing motorist—and on which success or failure greatly depends is the safety of the tyres. Considering that only a year ago it was thought that Segrave’s Sliced of about four miles a minute represented the uttermost limit which pneumatic tyres could be made to withstand, it is astonishing that it should ho found practicable by the makers— Dunlop Co., England —to design covers

For a speed which will probably be, at any rate from 15 to 20 m.p.h. or so higher. In order to prevent centrifugal forces from tearing the covens to pieces they have to be made as thin as passible, and yet must be strong enough to trasmit the enormous power of the 2000 h.p. engines from the rear wheels to the sand surface of the course Needless to sav, the factor of safety has to be cut rather fine. No one is nresent in the same room where these tyres are tested at Fort Dunlop. The'' - ' are whirled round a track on a revolving arm, driven, electrically, and the testers watch what happens through peepholes in a steel door. A system of remote controls enables them to adiust the speed and load, and they have ingenious indicators. which record temperature, the deflection of the cover and so forth. The life of a tyre when the maximum anticipated speed is reached is actually a matter of minutes, although, of course, the duration of the run—when the record is being attempted—in one direction over the measured mile, is completed in under a quarter of a minute, but the complete run in one direction is approximately nine miles. It is a striking tribute to the knowledge and craftsmanship behind the construction of these tyres, that Dunlop is selected by the world’s greatest sooed drivers, for tests that call for the finest and strongest tyres that the world has evolved.