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).
Blueprint diagram of clutch leverage and spring pressure for a synchro mesh system.
| Identifier | Morton\M13.2\ img130 | |
| Date | 6th November 1931 guessed | |
| 18.G.IV Clutch Leverage & Spring Pressure G54132 Clutch Spring. LOAD 125 LBS. Clutch. L.O.P. G54793 SYNCHRO MESH 13.100crs 2.250crs 2.650 3.125 .750 | ||