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).
Comparison of clutch data specifications for the Phantom II and Phantom III Spectre models.
| Identifier | ExFiles\Box 93\3\ scan0025 | |
| Date | 14th March 1935 | |
| 312 14. 3. 35 Clutch Data Phantom + SpectreCodename for Phantom III | | Position of Levers on 11 SH 4412 | Phantom II | Phan. III SpectreCodename for Phantom III N.G.Hs{Lord Ernest Hives - Chair} 4229 to 4404 | |---|---|---|---| | **Pedal Travel (Measured along chord at centre of Pedal Plate)** | | | | | Engaged (New) to Fully Out | 1 to 3 | 4.9" | 5.0" | | " (Worn, pedal right back) to Fully Out | 2 to 3 | 5.687" | 5.775" | | Pedal Movement taking up wear | 1 to 2 | .800" | .787" | | Radius to centre of Pedal Plate | | 16.750" | 13.000" | | **Plate Separation** | | | | | Engaged (New) to Fully Out | 1 to 3 | .092 | .092 | | Allowance for wear without Adjustment of Pedal | 1 to 2 | .015 | .015 | | Engaged (Pedal Right-back) to Fully Out | 2 to 3 | .107 | .107 | | Total Lining wear permitted. | 1 to 4 | .150 | .125 | | Thickness of Linings | | .250 | .125 | | Cushioning | | .005 + .10 | .015 - 5 | | **Leverage Pedal to Plate** | | | | | Engaged, New. | 1 | 54.2 | 55.5 | | Fully Out | 3 | 51.3 | 52.6 | | Pedal right back before first adjustment. | 2 | 55.2 | 56.5 | | Linings fully worn | 4 | 61.3 | 61.4 | | Average Leverage, (Pedal Travel / Plate Separation) | 1 to 3 | 53.3 | 54.4 | | Leverage from Length of Levers | | 56.0 | 52.6 | | ||