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 from The S.U. Carburetter Co. Ltd. regarding piston dampers, needles, and fuel discharge differences between jet sizes.
| Identifier | ExFiles\Box 121\4\ scan0227 | |
| Date | 29th October 1938 | |
| 1487 TELEPHONE BIRMINGHAM EAST 1171. TELEGRAMS: FLEXCARBUR, BIRMINGHAM. SU REGISTERED TRADE MARK THE SOCIETY OF MOTOR MANUFACTURERS & TRADERS LTD ENGINEERING & ALLIED EMPLOYERS' NATIONAL FEDERATION THE S.U. CARBURETTER CO. LTD. PROPRIETORS:- MORRIS MOTORS LTD. VISCOUNT NUFFIELD CHAIRMAN OLIVER BODEN, O.B.E. VICE-CHAIRMAN T. C. SKINNER, M.I.A.E. MANAGING DIRECTOR ADDERLEY PARK, BIRMINGHAM, 8. YOUR REF: Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}9/MH{M. Huckerby} OUR REF: BC/ER 29th October 1938. Messrs. Rolls-Royce Ltd., DERBY. File Dear Sirs, For the attention of Mr. C.T.Salt. Replying to your letter of the 27th inst. The spare piston dampers and needles were sent off last night which is a little after the date we promised them, but we hope that the delay has not inconvenienced you. Regarding the peculiar differences when using .090" and .100" jets, it is an exceedingly difficult matter to explain, and the only theory that we can advance is that the fan of discharged fuel is thinner with the larger jet, and is therefore more easily broken up by the air stream, and shortly, gives a superior discharge to the thicker fan of fuel using the smaller jet. This we know seems distinctly far-fetched, but as you know it is a fact that a wide spread thin discharge is far better than the comparative small volume of discharge which does not spread. Actually the difference is fairly marked between an .090" and 1/8" jet when giving the same fuel ratio, but unfortunately the measurements necessary when using a 1/8" jet would be impossible to reproduce as a manufacturing job. -1- | ||