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).
Test results and issues found with braking systems, axle control, and engine mountings.
| Identifier | ExFiles\Box 82\3\ scan0265 | |
| Date | 11th May 1935 guessed | |
| ( 7 ) Braking however with this scheme is more prone to shudder. This is due to the control of the Axle not being designed for the anchorage at the front. 3) STANDARD BRAKING SYSTEM WITH IMPROVED SERVO OF THE CRINKLY PLATE TYPE HAVING MODIFIED LINING FIXING. The servo has not given any proof of being more efficient than standard. The efficiency with heat generated during frequent use drops approximately 50%. This is the same as present standard. It recovers its efficiency in approximately two miles by the cooling effect. There were squeaks from the material for a short period. The latter part of the mileage there has been no squeaks. The condition of the servo was good when examined. 4) 14" BRAKE DRUMS WITH WATER EXCLUDERS. The 14" brake drums with the increased area of linings produced shudders and jaggers, which eventually after 1466 miles twisted the necks of the Axle. The fault was due to the increased leverage produced by the brake drum diameter and larger area of linings. The over-hung length of the Axle from the spring anchorage not being sufficiently strong to prevent the twisting effect. The Axle control for the same reason was of very little value. To incorporate 14" brake drums, the necks of the Axle require stiffening up, and the Axle control fixture moved 50% nearer to the neck of the Axle. 5) AXLE CONTROL TO N.SCH 4178 WITH AN ALTERNATIVE OF SPRINGS SHACKLED AT THE FRONT. The N.Sch.4178 has not been fitted. 6) STRENGTHENED FRONT AXLE TORSION SHAFTS TO N.SCH 4009. The shafts were quite satisfactory up to the time of the failure of the front axle. 7) RUBBER ENGINE MOUNTING LEG 2895 N.SCH.4167. The rubber engine mounting without a torque reaction damper fitted causes pulsations to be felt in the front seats. The lightened type torque damper fitted has smoothened the pulsations out. There is no sign of the engine having dropped or come out of alinement. Upon dismantling the front suspension, it was noticed that the diameter of the bush hole in the bottom rubber had increased approximately 50%. There appears to have been a scrubbing action taking place between the steel distance tube and the rubber. The bottom rubber block was only just in tension. It would appear that the top rubber blocks have given slightly, but not sufficient to cause the drop in front noticeable. The spherical stay from the pedals to the engine rear foot, does not hold the engine from moving endways. The Cylinder head is, under certain conditions, rubbing hard on the dashboard. The rear rubber buffers have to be set up two complete turns, to steady the movement of the engine and gearbox; otherwise the change speed gear lever rattles, and excessive movement of the pedals take place. | ||