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).
Two different arrangements for a supercharged unit's crankcase and crankshaft.
| Identifier | ExFiles\Box 140\1\ scan0124 | |
| Date | 29th January 1935 | |
| 4209 To RHC.{R. H. Coverley - Production Engineer} Hs{Lord Ernest Hives - Chair}/Smth.10/KW.29.1.35. Supercharged Unit. Confirming our conversation, we should like two crankcases and crankshafts produced for this unit. Each crankcase should have alternative faces for mounting the supercharger in any of the three positions previously instructed. Both crankshafts should be of the 7 bearing, narrow pin type. The dynamo drive ratio should be 1.5/1. Further details are as follows :- Arrangement 1. Rear main bearing longer and of larger dia. than standard, with 4 stud cap and stiffer rear panel as on 4 bearing engine. Flywheel flange stiffened (Hs.{Lord Ernest Hives - Chair}1737 att.). Otherwise standard. Arrangement 2. Rear main bearing and flywheel flange as in arrangement 1. Other journals extending the full width between the crank webs. Crankcase stiffened round the bearing bores, on the webs along the outside and elsewhere as on the four bearing engine. We shall need an adaptor to enable us to mount the dynamo in the standard position if required. We shall give you particularsof the flywheels in the course of a day or two when we have examined that on the Terraplane. It is possible that the clutch casing may have to be packed out in order to accommodate the stiffer flywheel flange. These two arrangements will enable us to proceed with the supercharger tests, and at the same time to experiment with flywheel flutter. Hs{Lord Ernest Hives - Chair}/Smth. Regarding Arrangement 2, we understand that the pattern for the 4-bearing case is still in existence. The simplest procedure will probably be to modify this pattern. | ||