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).
Details and specifications for front and rear springs for models 12.B.V and 12.B.IV.
| Identifier | ExFiles\Box 154a\2\ scan0236 | |
| Date | 18th January 1940 | |
| Copy to Olley. c. to Bastow. Rm{William Robotham - Chief Engineer}/C1m.1/JH.18.1.40. 12.B.V. Following are details of rear spring suitable for Length 50" Width 2". Poundage 950. Normal position ¼" negative camber. Deflection 7" Bump movement 3.5". Front spring eye 1.250" + 1 dia. Rear eye 0.994 + 1 dia. Front spring for 12.B.IV. Poundage at wheel 800. Deflection at wheel 8". Rate at wheel = 100 lbs.in. Leverage ratio = 1.724 Actual rate = 297 lbs/in. Normal load = 1380 lbs. when length = 7.183 Inside diameter = 4.252". Rm{William Robotham - Chief Engineer}/C1m. | ||