Comparison table of steering system specifications for various models and configurations.
| Identifier | ExFiles\Box 154\3\ scan0129 | |
| Date | 2nd February 1936 guessed | |
| COPY. Spectre(Codename for Phantom III). Spectre(Codename for Phantom III) revised. La {L. A. Archer} Salle. 20/25 with Spectre(Codename for Phantom III) box. 20/25 with revised spec.box. 20/25 suggested. 20/25 with Marles L.7. 20/25 RR. Steering. Phantom R.R. Steering. Helix angle. 6°35' 5°48' 7°30' 6°35' 5°48' 5°48' 8°37' 8°27' 7°15' Lead. .800 .700 .600 .800 .700 .700 .665 .700 .720 Column ratio. 15.32 17.5 18.75 15.32 17.5 17.5 21.3 12.55 13.10 Lever ratio. 1.062 1.062 .825 .997 .997 .872 .810 .997 1.135 Overall ratio. 16.3 18.6 15.5 15.27 17.4 15.25 17.2 12.5 14.85 Turns of wheel. 3.25 3.7 3.1 2.75 3.25 2.75 3.1 2.25 3.0 Pendulum Lever. 7.00 7.00 9.00 8.25 8.25 9.437 10.15 8.25 7.75 Pendulum Lever Angles. 77° 77° - 65° 65° - 52°45' 65° 71° | ||
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).