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).
Vibration tests conducted on the 18-G4 (C.7 Unit) with and without torque reaction dampers.
| Identifier | ExFiles\Box 137\4\ scan0131 | |
| Date | 1st December 1930 | |
| FOR FILES. X634 Dec. 1930. VIBRATION ON 18-G4. (C.7 Unit). (1) Torque Reaction Dampers Absent. Top Gear. On the drive there was a booming period at 38 m.p.h., not so noticeable on the overrun. From 54 M.P.H. upwards the engine was becoming rougher. Third Gear. There was a period commencing at 35 m.p.h. becoming rapidly worse at 38 (2800 R.P.M.) having a maximum at 42 and dying away at 45 m.p.h., at which speed the valves were bouncing. (2) Torque Reaction Dampers Absent) Whole running much Gearbox Support Absent. ) smoother than in (1). Top Gear. Torque reaction periods were bad at 10 and 12 m.p.h., on the drive a small period could be felt at 28 m.p.h. and a noise existed from 35 to 40. On the overrun there was a boom at 38 m.p.h. Third Gear. The ½ torsional period could just be detected 29-30 m.p.h. From 39-45 the "flywheel period" was then having a maximum at 42 m.p.h. (3) Standard Car with New Bearings and W.W. Flywheel. 3rd. Gear. The 42 m.p.h. period was now worst at 47 approx. but the valves were bouncing by then. This period was just detectable as beginning at 40 m.p.h. (3000 R.P.M.) but was of far smaller amplitude than with a standard flywheel. Hs{Lord Ernest Hives - Chair}/H.{Arthur M. Hanbury - Head Complaints} Grylls. | ||