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).
Engine starting issues, fuel quality, carburettor design, and the use of a choker.
Identifier | WestWitteringFiles\G\June1921\ Scan9 | |
Date | 8th June 1921 | |
To R.R. of America Inc. From R.{Sir Henry Royce} -3- R10/G8/6/21 Contd. arranged by Springfield was due to the changing of shape and not due to the heat, and was quite inconsistent[ly] heated or unheated. It has for many years been known that the throttle or induction pipe as near the carburettor as possible is the real place to apply heat. This has been confirmed and proved lately to be the only place where it is really effective. The recent lowering of the quality of the fuel has rendered a greater amount of heat necessary, and a sufficiently high temperature with really good gasoline seems only obtainable by use of exhaust, and we give the best scheme we have found. This seems comparatively easy and practicable but we do not know just yet whether this is sufficient or all we can do. Regarding starting, this seems to be entirely a question of getting evenly distributed throughout the cylinders continuously a sufficiently rich mixture of fuel and air. It does not require the engine turning at a high speed, and we believe the trouble can be completely met by the use of the extremely small additional carburettor, and the small bore pipe or pipes leading to the induction manifold. *I do not believe in a choker*, as it is apt to get the engine (in careless and clumsy hands) flooded with liquid gasoline, amongst other things sooting up plugs, and thus causing irregular firing, and also I do not think it advisable to attempt to run the engine at a higher speed by the starter motor because although the starter motor is sufficiently powerful and could be wound for a higher speed, or even be geared for a higher speed, it would make such a large drain upon the batteries that the trouble with the batteries would increase. Moreover, I do not think it at all necessary, and considering that we have a battery ignition, and [instead of] it a means of continuously getting gasoline into the induction manifold, with the extremely small carburettor (Contd.) [Handwritten left margin: X.3082] | ||