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).
List of required modifications and patterns for various engine and chassis components.
| Identifier | ExFiles\Box 3\4\ 04-page197 | |
| Date | 15th February 1933 | |
| (2) modification to the casting will be required on account of the modified dynamo. (6) Rocker Cover. The valve rocker cover will be different to the standard 20/25 to suit the J.l. type head, and will have the Bentley monogram cast on it instead of R.R. (7) Clutch Inspection Cover. A small pattern is required for this showing the Bentley monogram instead of R.R. (8) Induction Pipes. The pattern for the Bensport induction pipes for the S.U. carburetters is already made but slight modifications are required to the bend at each end on the patterns, and to the flanges holding the carburetters. (9) Cylinder Head. This is the existing J.l. cylinder head pattern, but slight modifications are required to the pattern to allow of trepanning round the inlet valve. (10) Clutch Casing. This is the existing 20/25 clutch casing but we wish to revert to the original practice followed in connection with this part,of having two different bosses for the brake pedal support which will require the addition of a boss to the existing pattern. (11) Engine Controls. These are naturally different to the 20/25 because of the different carburetters etc. A small pattern will be required for a control bracket. (12) Air Inlet Bend for S.U. carburetters. A pattern will be required for the air inlet connecting the two S.U. carburetters with the air silencer. (13) Fan Hub. The present experimental chassis has an adapter for modifying the fan hub to the correct length. A small pattern will be required for correcting this and rendering the adapter unnecessary. | ||