SOME WONDER CARS

Rotorua Morning Post, Volume 1, Issue 118, 11 January 1932, Page 6

SOME WONDER CARS

EXPERT CONSIDERS "WIZARD SMITH MAY REACH 260 M.P.H. ATTEMPTS ON RECORDS. A speed of 250 to 260 miles per hour should be attained Hy Mr. Norman ("Wizard") Smith when he attacks the land speed record at Ninety Mile Beach, according to the calculations of Mr. W. H. Bowen, a Wellington motor expert who has been associated with the late Major Sir Henry Segrave and the famous designer, Captain Irving. During a period of fifteen years when he was connected with the raeing department of the Sunbeam Motor Company, England, Mr. Bowen took part in famous continental races, including the French, Italian, and Spanish Grand . Prix,' as well as classic events in Britain. "Efforts of high speed drivers have been, and always will be, regarded as foolhardy, and many even be termed useless by individuals who consider no reward great enough to compensate for the risk to human life and limb," said Mr. Bowen in an interview with a "Post" reporter. "It is indeed these risks which are continually spurring the few to fresh endeavour."

The Quest for Speed. Referring to the maximum speed records, Mr. Bowen said that the rate of progress in the design of high speed engines during the past few years was nothing short of fantastic. Since 1925, when Malcolm Campbell startled the world by attaining just over 150 m.p.h., the maximum speed on land had increased by 95 m.p.h. Since the beginning of 1925 the following speed records had been established:— 1925 July. — Malcolm Campbell (Sunbeam), 150.760 m.p.h. 1926 (April) — Parry Thomas (Thomas Special), 168.075 m.p.h. 1926 (April) — Parry Thomas (Thomas Special), 170.624 m.p.h. 1927 (February). — Malcolm Campbell (Napier Special), 174.224 m.p.h. 1927 (March). — Major H. O. D. Segrave (Sunbeam), 203.790 m.p.h. 1928 (February). — Malcolm Campbell (Napier Special), 206.956 m.p.h. 1928 (April). — Ray Keech (White Triplex), 207.502 m.p.h. 1929 (March). — Major Segrave (Ir-ving-Napier), 231.362 m.p.h. 1931 (February). — Malcolm Campbell Napier Special), 246.090 m.p.h.

It would be seen from these records, said Mr. Bowen, that Sir Henry Segrave made the greatest "jumps" with 30 and 24 miles per hour respectively. His performances were indeed a great achievement for man and machine. Much valuable data was gathered from these attempts, one of the most important items being the importance of reducing the head resistance to a minimum. This reduction of resistance, by streamlining, had played a very important part in attaining a speed of over 400 m.p.h. in.the air. As an indication of the magnitude of head-on resistance, Mr. Bowen said that Segrave's "Golden Arrow" when travelling at 250 m.p.h., used 65 per : cent. of its efficiency in overcoming this pressure. Value of Speed Tests. "Valuable data gained in high speed work is soon shown in a modified form in ordinary production models," continued Mr. Bowen. "Take, for instance, the recent 500-mile race at Brooklands, when stock models as supplied to the public averaged over 100 m.p.h., including 'baby' cars. These cars are a charm to handle at such speed, and perfectly safe. Their wonderful performance is due almost entirely to experience gained in recordbreaking attempts." Improvement on "Golden Arrow." Mr. Bowen is of the opinion that the modification to the rear and general streamlining of ' Mr. Smith's "Enterprise" was a step in the right direction, since the car should be steadier than the "Golden Arrow." The latter car was capable under the best beach and weather conditions of 250 m.p.h. Under ideal conditions Daytona sands presented a tractive resistance of 60 pounds per ton, but when Segrave made his record the resistance was 85 pounds per ton. "I am assured that the New Zealand beach is better than Daytona, so Mr. Smith should attain a speed of 250 to 260

m.p.h. and so spur on Malcolm Campbell to visit the Dominion, and also the Sunbeam 'Silver Bullet' with Kaye Don at the Wheel." Mr. Bowen then referred to the great cost of preparing record-break-ing cars, and gave the following figures in connection with the "Golden : Arrow": — Design and drawing office expenditure £2228 4s 7d; engine (Napier 12-cylinder), £3078 10s; gear box, £495 14s lld; clutch, £159 8s 7d; radiators, £604 7s 7d; wind tunnel, model and laboratory tests, £148 2s; body framework, £89 5s; road springs, £21; electrical equipment, £53 8s 6d; rear axle, front axle, brakes and chassis assembly, £2566 6s 4d; wheel balancing, £43 5s; sundry expenses, £31 10s; value of parts given .free (such as accessories, etc.), £1500; total cost of car, £11,599 15s 4d); transport from England to Daytona beach, £2000. The Power that Drives. The following interesting data relating to the engine of .the "Golden Arrow," which is the same as that installed in Mr. Smith's machine, were also given by Mr. Bowen. — Engine. Napier 12-cylinder, bore 5|in, stroke '5 l-8in, capacity 23,942 cubic centimetres, or 1461 cubic inches. Maximum power output (tetraethyll'ead petrol used), 938 h.p. at 3400 revolutions per minute. Maximum number of revolutions per minute (short periods), 3600. Coippression ratio, 10 to 1. Fuel used on run, alcohol, owing to less risk of fouling plugs. Fuel consumption, 6.7 pints per minute at 3300 r.p.m. Speed on gears at 3400 r.p.m.: First (3 to 1 ratio), 78 m.p.h.; second (1.54 to 1), 156.5 m.p.h.; third (1 to 1), 241 m.p.h. The allocation of milable brake

horse power at 250 m.p.h. was calculated to be as follows: — Head resistance, 65 per cent., or 585 b.h.p.; mechanical losses, 18.3 per cent. or 165 b.h.p.; tractive resistance, 16.7 per cent. or 150 b.h.p. At 231.26 m.p.h. the speed of the "Golden Arrow" equalled 339.5ft per second. If put in neutral at that speed and not braked the car would travel 4 miles in approximately 2min. 4sec., with the brakes applied it would pull up in approximately one mile, . in 31 seconds. At 231 m.p.h. the tyres made 33 revolutions per second; this was equivalent to a stationary tyre being struck 33 times per second in the same place with a force of threequai'ters of a ton.