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).
Performance graph comparing standard 4-speed and proposed 3-speed gear ratios for a Spectre vehicle.
| Identifier | ExFiles\Box 94\1\ scan0153 | |
| Date | 5th December 1934 | |
| SPECTRECodename for Phantom III WITH STD. 4 SPEEDS AND SUGGESTED 3 SPEEDS FOR RELAY. AXLE: 4.25:1 TYRES EFFECTIVE RADIUS: 14.7" POWER CURVE: HS{Lord Ernest Hives - Chair}/RM{William Robotham - Chief Engineer}4/KW 5-12-34 COMPLETE SILENCERS 3% DEDUCTED FOR GEARBOX LOSS. CURVES FINISH AT 4500 RPM Y-AXIS: POWER AT PROPELLER SHAFT X-AXIS: ROAD SPEED M.P.H. TABLE DATA: STD. RATIOS: .760 .503 .37 PROPOSED ": .710 .44 MAX EFFECTIVE SPEEDS: 58 43 29 56 38 SPEEDS AT 4500 RPM: 93 71 47 34 93 66 41 ANNOTATION: NEW 5-7-35 | ||