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).
Modifications to the Spectre Governor Spring with dimensional specifications.
| Identifier | ExFiles\Box 4\1\ 01-page209 | |
| Date | 7th January 1935 | |
| TOTAL NO. OF COILS - 2 DIA OF WIRE - .064" = 16 S.W.G LOAD WHEN TWISTED FROM INITIAL ANGLE OF 74° TO 97° - 38.5 TO 4 LBS AT RAD .875" MOD'N TO GOVERNOR SPRING (SPECTRECodename for Phantom III) OTHER DETAILS SEE (E57915) ROLLS-ROYCE LTD DERBY 0.925 +/- 0.005 INSIDE DIA 1.053 MEAN DIA 1.181 OUTSIDE DIA 1.250 DIA 3 COILS 74° +/- 1° 103° +/- 1° LDS 2.1.35 | ||