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).
The standardization of the Zenith petrol filter for the 20 HP car, including specifications for plate gap and weight.
| Identifier | ExFiles\Box 44\1\ Scan153 | |
| Date | 1st June 1927 | |
| To BY.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} X3700 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}4/LG2. 6. 27. ZENITH PETROL FILTER. We are in the process of standardizing the Zenith petrol filter for the 20 HP. car. The filter we have tested in France has a gap of .05 mm. between the plates. This will be the gap we should like to be used on production. We are trying to make the Zenith filter people reduce the weight of their filter as at present it weighs 1 1/2 lbs., but they do not seem very anxious to deviate from one single standard. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||