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).
Modifications to the Phantom III reverse throttle carburetter's lightened throttle spring.
| Identifier | ExFiles\Box 93\2\ scan0102 | |
| Date | 4th October 1935 | |
| To Hs{Lord Ernest Hives - Chair}/GWH.{George W. Hancock - Head Chateauroux} 4308 E/PSN.3/MN.4.10.35. Copy to BY.{R.W. Bailey - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} PHANTOM III. Reverse Throttle Carburetters - Lightened Throttle Spring. We send you herewith a print of LeC 4742 giving particulars of the throttle spring loading and the torque which should be exerted on the throttle spindles, and also on the accelerator pedal. The scheme shows a link lengthened by .14" which should reduce the throttle spring closed torque by 25%. We should be pleased if you would fit this lengthened link to see whether the reduced throttle spring load is adequate. We note that you have done some tests and found that the load of the accelerator pedal is 10 lbs. with the present arrangement and springs, instead of about 5 lbs. as is usual on R.R. cars. We confirm that we have pointed out to you that there does not appear to be sufficient toggling in the throttle controls to the accelerator pedal, and understand that you are going to get this looked into with a view to obtaining the maximum possible toggling. We will also look into the possibility of moving the spring anchorage into such a position that the springs will be horizontal and the spring load will subtract from the suction load on the throttle spindle bearings in the tick-over position, as was done on the Phantom II with some succes. E/PSN. Att: Print of LeC.4742. | ||