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).
Valve spring lengths for a Wraith III engine valve gear.
| Identifier | ExFiles\Box 10\3\ 03-page021 | |
| Date | 18th January 1937 | |
| To E.{Mr Elliott - Chief Engineer} c. to E/PSN. c. to Rm{William Robotham - Chief Engineer}/Sadl. 654 Rm{William Robotham - Chief Engineer}/Mths.{Reg Matthews}9/JH.18.1.37. Wraith III Valve Gear. Further to our report Rm{William Robotham - Chief Engineer}/Mths.{Reg Matthews}9/R.16.3.37. we give you the following details of valve spring lengths in the valve closed position, for the springs tested in above report. No.1 cyl. Inlet 1.575. Exhaust 1.550. No.2 cyl. Inlet 1.625. Exhaust 1.575. No.3 cyl. Inlet 1.600. Exhaust 1.525. No.4 cyl. Inlet 1.515. Exhaust 1.575. No.5 cyl. Inlet 1.575. Exhaust 1.550. No.6 cyl. Inlet 1.550. Exhaust 1.625. The normal valve closed length should be 1.525. Rm{William Robotham - Chief Engineer}/Mths.{Reg Matthews} | ||