Rumblings, November 1946

Spider
One of the most interesting happenings at this season’s sprint events was the return of Basil Davenport’s famous Spider, which climbed Shelsley Spider Walsh in 45.65 sec. to win the 1 1/2-litre class and make fastest time by an unsupercharged car at the first post-war climb. This ascent was the fastest of all those great runs in this car which Davenport has made at Shelsley Walsh, with the exception only of his time of 44.6 sec. put up in 1930 when competing against Stuck’s 3-litre Austro-Daimler. The successful re-appearance of this famous sprint car has naturally aroused much controversy. A lot of people thought that G. H. Symonds had acquired the Spider, but actually the car he raced immediately before the war was Davenport’s 2-seater practice car, in which he used a 2-valve-per-pot engine, but which Symonds ran with a new body copied from the Davenport single-seater and in which he installed a Davenport 4-valve-per-pot engine. We are glad to be able to sort things out in Davenport’s own words. Here is what he writes: —

“The car I am now running is my original ‘Spider,’ which was assembled by me in 1923. The chassis was purchased from the Frazer-Nash works, who at that time were in London Road, Kingston-on-Thames. The body„ which I made myself, was on the same style as that of Kim II, a car used by Captain Nash with great success in 1920/21.

“During 1924 I used a 2-valve-per-cylinder, o.h.c. engine of 1,100 c.c. This engine had the camshafts driven by a chain it the rear of the cam boxes, on the same lines as my present engine. About this time I was fortunate in being able to purchase from Captain Nash a 1,500-c.c., 4-valve-per-cylinder engine, out of a car called “Mowgli,” which had lapped Brooklands at over 90 m.p.h. in 1922, a very good performance in those days. I started racing with this engine in 1925, and it was the basis of all the success I had from 1926 to 1930. I knew I was on the right lines when, at a Southport meeting in 1925, I did 92 m.p.h. over the measured mile. At Shelsley that year I was unfortunate, as the big-end broke up 100 yards from the finishing line, and I had to free wheel the rest. Even so, I was only half a second slower than Segrave’s Sunbeam. After this performance, I was convinced that with luck I could make f.t.d.

[Another fine performance of Davenport’s in 1925 was f.t.d. at Colwyn Bay.—Ed.]

“With the experience gained in 1925, I discovered the method of keeping a V-twin engine running correctly and in one piece for the distance of one mile.

“At Shelsley, between 1926 and 1929, I won seven consecutive climbs, comprising three trade and four amateur events.

“In 1926 my time was 48.8 sec., ending in 1928 with 46.4 sec., all on a flint surface.

“In 1930, against Von Stuck, I did my best time of 44.6 sec. on the tar road, as it is to-day, but with hand-signalling at the start. Although beaten by Von Stuck, I remain more pleased with this performance than any.

“From 1926 to 1930 the modifications to ‘Spider’ were as follows: first, I used one carburetter, a 40-mm. Solex, and petrol-benzole fuel. In 1927 I had two carburetters and used R.D.1, with an 8 to 1 compression-ratio and new camshafts. In 1930 I got up to a 10 to 1 compression-ratio. Of course, various parts were substituted as the old ones gave out, which was fairly often.

“Originally I used forked connecting rods. This practice is universal on all V-twin motor-cycle engines, and it gave me a lot of trouble. The rods occasionally broke just above the fork, with disastrous results. In 1927 I made the chief alteration to the engine, by advancing the right-hand cylinder 3/4 in. and using two single rods side by side, which eliminated any further trouble.

“After Von Stuck’s time of 42.8 sec. in 1930 it was obvious I would have to try to go quicker.

“Dr. G. Mucklow, now Professor of Engineering, Birmingham University, designed new cylinder heads, to replace the original ones which were of light construction in aluminium bronze and inclined to warp. The new heads worked in with the existing cam boxes and layout, and were fitted in 1931, together with front wheel brakes. I ran twice without success (46.2 and 49.2 sec.) and then, owing to pressure of business, I retired from the game in 1931.

“With the ending of the war, and the encouragement of G. H. Symonds, who had previously bought my spare car with a 2 valve o.h.c. engine, I decided to have another try. In this I was fortunate in having the help of my two younger brothers, A. C. and M. E. Davenport, both very clever mechanics and well-known racing motor cyclists. We had to build the car up from scratch, as the engine had been taken down when I retired in 1931. We soon discovered the reason for, and remedied, the fall in speed experienced during that year.

“At present I am using a compression-ratio of 11 to 1 with alcohol fuel. The engine will do 5,000 to 5,500 r.p.m., and the three ratios I use at Shelsley are 10 to 1, 6.6 to 1, and 5.2 to 1, which give maximum speeds of 45, 66 and 75 m.p.h., respectively. The rear wheels are fitted with 16 by 5 tyres and the front with 19 by 4, which I considered the most suitable of those available at the time. The weight of the car is 10 cwt-.

” I find it very interesting returning to racing after an interval of 15 years, and hope to get ‘Spider’ going faster next year.”

We certainly hope you do, B. D. H., for you deserve your successes, if anyone does.

Discussion
Last month Rivers Fletcher put over another “Rembrandt” luncheon and discussion. This time Oliver Bertram took the chair, and very ably did he conduct the meeting, which took the form of a discussion on problems bearing on the future of competition motoring. A sort of informal version of the R.A.C.’s Meeting-of-the-Clubs, as it were. Such subjects as international racing, the G.P. formula, ex-enemy competitors, G.P teams for Britain, and kindred subjects having been declared taboo, the discussion developed around such things as scrutineering, handicapping, what is a sports car? and the Technical Press.

Major Dixon Spain spoke first, by way of introduction, stating that this year the R.A.C. had issued 600 competition licences, vetted 20 courses, and sanctioned 34 speed events. He warned organisers against the fearful fuss that would follow a fatal accident to a spectator at such meetings. Those present (their ranks somewhat depleted by the Horndean sprint on the same day) then debated whether sports and racing cars should be allowed to run together in the same event. Credit goes to Ian Connell for the best suggestion — let the racing cars have their second runs immediately after their first runs, while engines are warm, opening and concluding the meeting with the sports-car runs. This would save hanging about with temperamental machinery and enable cars to be packed into vans and on to trailers earlier than is now the case. It might also materially assist in getting the fast cars two runs over a dry course. Thank you, Connell!

On the subject of handicapping, Philip Turner put in a word for individual handicaps (B.A.R.C. fashion), but everyone else was against it. Someone suggested grouping cars into different classes on the basis of performance, irrespective of type of car, driver, etc. A matter which was not discussed but which should have been, was whether capacity classes at sprint meetings should be standardised, or the sub-divisions left to the discretion of the different organisers. Personally, we rather like the spice of variety which results from the existing haphazardness. The debate on scrutineering didn’t get anywhere in particular, and the age-old question of what is a sports car acted as a red herring across the trail. On the subject of race reports in the Technical Press, Laurence Pomeroy said he would like to lie in a slit at the side of the course, the better to watch i.f.s. in action. That concluded the official meeting

We hope these Rembrandt meetings will continue to be an annual fixture — but rather later in the year when no active participation in the Sport is to be had elsewhere.