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).
Gearbox, clutch, and exhaust system performance during testing.
| Identifier | ExFiles\Box 22\3\ Scan088 | |
| Date | 25th February 1932 | |
| -5- When running down a steep gradient of approx 1 in 6 in top gear a change down to 1st gear was made without accelerating the engine by the throttle; the change was made without producing any sudden shock although severe retardation was accomplished, the rear wheels locked momentarily during the process of retardation. It is not possible to pick up a dead engine by engaging top gears at any speed below about 15 m.p.h. Phenominal slow running in top gear is of course possible. The slipping of the flywheel although a little strange at first is not at all objectionable when one has got used to it, there does not appear to be any slipping above about 30 m.p.h. In one or two instances failures occurred which appear to be due to some mechanical defect :- A few instances after attempting to change gear the clutch pedal came right up out of position, about twice its normal travel, when in this position no gear is in engagement and considerable pressure has to be executed to push the pedal back again. Once when changing from top to 3rd gear, after depressing and releasing the clutch pedal the box was found to be in neutral, after a second depression of the pedal the correct gear was engaged. Apart from these no trouble was experienced; it is noticed however that it is necessary to depress the pedal to its limit every time a change is required. A rough test in the garage made by running the engine up in the various gears (the car being stationary) showed that slipping of the gear brake bands can and does occur in reverse gear, 1st gear and very slightly in 2nd gear. Exhaust System. A Burgess silencer is employed and is quite good; there is no appreciable noise from the exhaust noticed when inside the car, the external noise is perhaps slightly more than we should tolerate and is noticeable when driving along a road with a high wall near the roadside. This type of silencer consists of a straight through pipe drilled liberally and surrounded with metal wool, it is a type in which there must be very little power loss and appears worth while investigating. | ||