From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Letter to the S.U. Carburetter Co. discussing the performance and trial of their carburetter on a 25 HP car unit fitted to a tank.
| Identifier | ExFiles\Box 31\4\ Scan189 | |
| Date | 4th July 1932 | |
| c. E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}3/AD. July 4th, 1932. X1487 The S.U. Carburetter Co. East Works, Bordesley Green Rd. Adderley Park, Birmingham. For the attention of Mr. Skinner. Dear Mr. Skinner, Thank you very much for the petrol lifts. There is a job which might interest you on our 25 H.P. car unit. You probably did not know that we have fitted one of these to a tank. It runs well but the Rolls-Royce carburetter with the air valve exposed to the incoming air sticks due to the enormous amount of sand etc. which the tank/churns up. track A proposal is to use a Solex carburetter but we do not like the idea at all as the Solex is not nearly so good as the S.U. in most respects. The question is whether the S.U. will suffer from the same defect as our own carburetter and we believe it is worth while giving it a trial at any rate and we are therefore proposing to fit one to the tank. Now we have never had an S.U. fitted to the 25 HP. car which had the best combination of needle and piston as approved by your own people. we played about with the avail-able pieces here and achieved a fair measure of success with the brass piston weighing 1 lb. 2 ozs. and W.O.2 needle. Though this needle is definitely on the rich side, judging by the petrol consumption which is about 14 on the S.U. compared with 16 on our own carburetter, there is a definite weakness round about 30 M.P.H. Therefore we know that the carburetter is not quite right. | ||