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).
Specification document detailing modifications to the Bentley III induction system.
| Identifier | ExFiles\Box 99\1\ scan0009 | |
| Date | 28th April 1938 | |
| 121 Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}9/JH.28.4.38. BENTLEY III INDUCTION SYSTEM. Suggestion Latest Specification. Induction pipe EB.3477-8 to be modified as follows - Carb. flanges. Stud centres etc. altered to suit H.4 type carburettors (1.500 throttle) Auto start connection. The centre restriction connecting the two halves of the induction pipe, to be replaced by a detachable centre piece which will have a boss to carry a union. The two halves of the induction pipe to be connected by a .375 balance hole drilled through the centre of the connecting piece, and the starting mixture will also be distributed from this passage. Thermostat control. The rear hot spot to be modified to provide a housing for the thermostat type U.S. 35° C.A. This should be on the underside of the hot spot. This housing will be in effect, a recess, into which the thermostat fits, but water must not be in contact with the thermostat casing. Carburettors. S.U. type H.4 as supplied by the S.U. Co. The question of finish, and steel throttle bushes, etc. will be progressed as we gain experience with the carburettors in use. Controls. To ECD.617-8 except for mixture control levers. For the present we can use, and connect up to the levers supplied with the carburettors. Air intake. The flanges must match up with those of the H.4 carburettors. Petrol drains. Two drains only are required. (1) From the top of the floatchamber (.187 bore). (2) From the air intake bend. | ||