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).
Gear ratio and operational start date for a 20 HP experimental car.
| Identifier | ExFiles\Box 180\M2\M2.7\ img024 | |
| Date | 8th February 1927 | |
| S/W. To Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} CWB. EP.{G. Eric Platford - Chief Quality Engineer} X.53400. PN{Mr Northey}4/EH8.2.27 X.5350 With regard to the 20 HP. Experimental car which it has been decided should be run for 10,000 miles, I would like to know the approximate date when you think this will start on its operations, and also what will be the actual gear ratio of the axle. So far, we understand that this may represent half a tooth less than the standard and that with the medium pressure tyres a further half tooth will be realised. Personally, I much fear that this small amount of lower gear ratio will not be sufficient to improve the performance of this model under general running conditions, and I should like to know from you whether any further reduction of the gear ratio is likely to be feasible or put on test. PN.{Mr Northey} | ||