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).
Power output chart for the 20/25 model comparing different cylinder block and carburettor configurations.
| Identifier | ExFiles\Box 102\1\ scan0188 | |
| Date | 22th June 1934 | |
| 20/25 POWER OUTPUT LIST 37 COMP RATIO 5.8:1 CAMSHAFT ES.777 (.02") 1 5/8" HORIZONTAL CARB. (AEC3488) (1) CYL. BLOCK ES9726 (OVAL PASSAGE) (2) PASSAGE INCREASED IN DIA TO 1.200" (30% INCREASE IN AREA) (3) CYL. BLOCK LEC 3795 (OVAL PASSAGE) (60% INCREASE IN AREA) DIAGRAM: TDC 15° 34.8° 33.6° BDC (TAPPETS .010") (F.T.S.) | ||