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).
Progress report on engine idling, brake adjustments, and ongoing suspension problems.
Identifier | ExFiles\Box 4\1\ 01-page251 | |
Date | 7th February 1935 | |
-2- (3) Cont'd.{John DeLooze - Company Secretary} It is not of course an easy job to set the idling of an engine fitted with 4 carburetters. We are therefore running the car with the present setting for a few days to see whether the slow running deteriorates. If the slow running is maintained, then the fact that adjustment is not easy does not matter very much. NEW ADJUSTMENT (4) Now that we have locked the adjustment up the brakes are improved sufficiently to make the car quite safe to drive about. We have previously pointed out that we consider the trouble with the brakes was chiefly due to this adjustment. The design modifications to this adjustment will be on test shortly: we doubt, however, whether these will overcome the difficulty. Until we have got rid of the inefficiency in the adjusting mechanism we shall only get good brakes by locking the adjustment up. The fact that we have for the first time had some front brakes has indicated that with 10" deflection front springs the front of the car dips alarmingly when pulling up sharply. This is probably emphasised by the Hotchkiss control of the back axle. It adds another reason for not using very low rating front springs. (5) The modified sump as reported on by GWR, appears to be completely effective in eliminating loss of oil pressure. (6) The new manifold to Lec.4164 is slightly better than the original one but as this amounts to only 1% it is not of major importance. We are circulating a separate report. The suspension remains the most difficult problem, being divided into two parts - (a) the behaviour of the car over hump-backed bridges, and (b) the continual shaking of the frame on wavy road surfaces due, as far as we can see, to shocks transmitted to it by the wheels. We understand from Leslie that when they put custom built bodies on some of the Buicks in Paris, the sideways movement of the dashboard was appreciated as being a problem. Some Americans of course have fitted rubber to the Wishbone suspension to remove the rigidity of the scheme. For the time being we are concentrating most of our energies on these latter two problems. Ha/Rm.{William Robotham - Chief Engineer} | ||