Tommy Sopwith's Sphinx

The new sports-racing car known as the Sphinx, which made its debut at Goodwood on March 27th, gaining second place to an XK120C Jaguar in one race, is owned by Tommy Sopwith, junior, 21-year-old son of Sir Thomas Sopwith, C.B.E.

The Sphinx is entered by the Equipe Endeavour, named after Sir Thomas Sopwith’s racing yachts of the mid-‘thirties, which were challengers in the America Cup Race. The stable uses Sir Thomas’ colours of dark blue, with an edging of gold to differentiate the son’s colour from his father’s.

Operating from Coventry, the Equipe Endeavour is not officially sponsored by Sir Thomas’ Armstrong-Siddeley interests, although staff from this factory devote their spare time to working on the car. Tom Sopwith is himself a post-graduate apprentice at Armstrong-Siddeley, having joined his father’s firm in this capacity after service at home and in Egypt with H.M. Coldstream Guards, which he entered after his education at Stowe School terminated — incidentally, what a lot of prominent motoring sportsmen Stowe has produced.

The Sphinx was completed in three months, but was badly damaged during a practice crash. Nevertheless, it was ready for the opening Goodwood meeting and Oulton Park and may run at Silverstone this month.

The engine is an Armstrong-Siddeley Sapphire Six of 90 mm. by 90 mm. (3,453 c.c.). It has been modified to produce, it is said, over 200 b.h.p. at 5,200 r.p.m. Carburation is by triple twin-choke Webers and ignition by a Lucas high-duty coil.

Instead of building a special chassis for this special Sapphire engine Sopwith bought from Sydney Allard a JR Allard with de Dion back axle. An Armstrong-Siddeley electric self-change epicyclic gearbox is retained, with normal ratios, and for its first races a back-axle ratio of 3.55 to 1 was used, in conjunction with 6.00 by 16 Dunlop racing tyres.

Tom Sopwith also drove a Sapphire saloon in the closed-car event at the first B.A.R.C. Members’ Meeting of the year. Next season the Equipe Endeavour hopes to race a team of Sphinx sports-racing cars.

In the past the marque Armstrong-Siddeley has performed well in long-distance rallies and we are very glad to know that these famous English cars will be represented in modern racing. — W. B.