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 modifications and design statuses for various components, comparing the Phantom II and 20/25 models.
| Identifier | ExFiles\Box 30\2\ Scan344 | |
| Date | 9th December 1933 | |
| - 4 - Modification. P.II. 20/25. (23) Accessible Easy operated brake adjustment as Bentley. Design nearly completed for rear. Design in hand for rear. (24) Clutch improvements. Wider friction faces, M.S.presser plate. Reduced friction of operation by knife edge or needle roller bearings. Designs required. Designs required. (25) Improved change speed lever. Design required. As Bentley. (26) Rear Axle Ratio. ------- 5% lower ratio required for increased body and chassis weights. (27) Radiator Fan. More silent fan required. Design required. Design required. (28) Petrol Pump. ------- Similar unit may be required as Bentley but with modified base to suit 20/25 dash. (29) Petrol Tank. 28 gallon tank to simplified design recently issued by BY.{R.W. Bailey - Chief Engineer} This tank should be fitted with sealed filler and vent. Tank to be fitted with sealed filler and vent. (30) Dropped front crossmember with head lamp pillars outside frame as fixture and starting shaft and handle relegated to kit. Design required. No Design required. | ||