No. 7—The Arab
When talking with Mr. Stroud about the Adams car, as reported in the previous fragment in this series, he mentioned that he worked for a time with Reid A. Railton on the short-lived Arab car, which had a long-stroke 2-litre engine similar to those used by Parry Thomas, the great Brooklands exponent.
The Arab was Railton’s brainchild, and was assembled largely from proprietary parts—Mr. Stroud mentioned Perrot front brakes and Moss gearbox and back-axle. Apparently only ten cars were budgeted for in the first place and the sad fatality to Thomas at Pendine early in 1927 so upset Railton that he paid off his workers and closed the little factory. Mr. Stroud still has the last cheque for his wages, which, sentimentally, he asked Railton to give to him after it had passed through the bank.
The Arab engine incorporated the ingenious Thomas valve gear, whereby one cam operated both inlet and exhaust valves, which were closed by a common leaf-spring. Incidentally, although Parry Thomas does not appear to have had any connection with the Arab, these laminated valve springs were taken to Brooklands for him to supervise the hardening and tempering of them.
At first Railton rented a steel foundry works in Letchworth but later he moved the small Arab factory to the old Phoenix car premises in the same town. A famous steel foundry near by machined the castings.
There were one or two notable items of Arab specification. For instance, tension of the timing chain driving the overhead camshaft could be adjusted simply by operating a lever placed behind the radiator, which functioned, on the ratchet system, on the jockey sprocket of the long chain which drove the o.h. camshaft, water and oil pumps, magneto and dynamo. Then the road springs were attached to the chassis by adjustable mountings, pains being taken to ensure that springs and chassis were absolutely in line before the mountings were dowelled in position. This factor resulted in excellent roadholding. The clutches were made in the Arab works, and here each engine was run on a test bed. Railton, recalls Mr. Stroud, had an uncanny gift of hearing the tiniest defect before anyone else in the test house was aware of it. For example, once, when rotoscope checks were being made at 4,000 r.p.m. to discover whether the valves bounced. Railton ordered an engine to be switched off, because he had heard the dynamo seize momentarily !
Every Arab made was taken out on test by Railton himself. One fault which developed in a car sold to the son of a famous diamond merchant was failure of the high-level oil pump to feed oil past the cooling tunnels in the big sump. One Arab was fitted with four separate carburetters for speed tests on Brooklands Track.
As far as Mr. Stroud recollects four Arabs were completed and sold and there were three or four nearly complete when Railton lost interest. The Arab was described in the motoring Press in November 1926 and ceased production after March 1927.—W. B.