ASHBY'S ALFA DEVELOPMENTS

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ASHBY’S ALFA DEVELOPMENTS

When we visited A. F. Ashby to glean some information on the timing of the Riley marque, we were invited to examine the 3.2-litre monoposto Dubonnet suspended Alfa-Romeo which Ashby acquired from the Scuderia Ferrari last year, taking delivery in time to record 3rd fastest time at Brighton at 76.27 m.p.h. It is fairly common knowledge that the Alfa-Romeo cylinder blocks have given considerable trouble—Shuttleworth, for one, admitted defeat in this respect— and Ashby’s car had this bother in the Campbell Trophy Race this year. This was rectified, but a piece of broken valve guide had lodged beneath the retaining bolt of the blower-release valve, and when Ashby really opened out in practice on the Friday before the International Trophy Race it became dislodged and entered No. 3 cylinder with unhappy results. After this Ashby decided to entirely redesign the cylinder heads and blocks, using knowledge gained in the development of his ” flat-iron ” Riley Nine, the Alfa heads and valve layout being very similar to that of the Riley and the bore almost identical. As in the Riley experiments, Ashby bases his calculations largely on single-cylinder practice. We have seen drawings of the new head design, but naturally our lips are fairly fully-sealed. However, it may be disclosed that the new blocks (with fixed heads, as before) will be of iron and not light alloy and twenty modifications will be made in the head design alone. These include new shape ports, 14 mm., unmasked, newly-positioned plugs and very special attention to the water flow, which will have separate off-takes by each exhaust valve. The blocks will be attached to the crankcase by a new method. Special con-rods have been. made, with stiffening ribs on the big-ends, in accordance with patents granted to Ashby in 1934. The blower pressure will remain at about 12 lb. per square inch, but a new system of distribution will be used, probably incorporating separate delivery branches. New pistons have been designed. Some mysteries in respect of lubrication have also come to light recently. Mr. Ashby does not hold much brief for the power-outputs commonly claimed for modern G.P. units,* and believes that his Alfa engine, before modification, only gave about 175 b.h.p., still a creditable output for so large a

unit. He hopes eventually to release 300 b.h.p. After modification the engine will be of 3-litres capacity, to comply with the new Formula, with which Ashby is in favour. Asking how he would use the additional weight allowance we were interested to learn that the Alfa already weighed over 15 cwt. when delivered, although built to comply with the 1934-7 Formula. Ashby finds the Dubonnet independent front suspension of great value. He contemplates racing at Brooklands and Doningtou next year, but we gather he has little use for the Crystal Palace circuit.