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).
The development and testing of adjustable venturi, throttle, and pilot jet systems.
| Identifier | ExFiles\Box 74\2\ scan0032 | |
| Date | 9th September 1921 | |
| Contd:- -2- Hs{Lord Ernest Hives - Chair}4/LG13.9.21. ------------ extravagant to have the adjustable venturi and the choke on the throttle. So far we have not been able to use the adjust-able venturi at all; we have had to keep it open to the fullest extent. We cannot foresee any condition where it would be necessary to use both adjustments. As we have pointed out previously, we have obtained our best results with the little automatic pilot jet which sits on the induction pipe. We have noticed lately another advantage with this scheme, and that is, it overcomes the fault which we get with the fixed pilot jet of the risk of the engine stopping when the main throttle is open. The main throttle requires careful opening up to avoid this. With the automatci one, as soon as the main throttle is opened up, the throat becomes smaller and the mixture is enriched compared with the fixed pilot jet. We are hoping to send to Springfield an exhaust heated throttle and all controls by the end of this week but the pilot jet is not yet in a fit state to send. We recommend that another pilot jet is instructed with the areas of the passages doubled. Hs.{Lord Ernest Hives - Chair} | ||