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).
Fuel consumption road test comparing a single jet with a two jet setup.
| Identifier | ExFiles\Box 147\5\ scan0005 | |
| Date | 23th April 1908 | |
| X459 3800 (2500) Consumption test on road comparing 2 jet v single jet large jet. Coker's home 23/4/08 on 742 Work to Allingha road. 3 up & 6 bags. 3rd gear 8.5 miles per 2 qtr. air vol lift 1/8" Round Swann min course, 3rd gear. 18 mph hr. per qt. 4.2. 4th gear 4.8 30 mph hr. per qt. 3.7 all out? 40 mph hr. qt. 3.2, 4th gear 3.5 2 jet Return of above road 3rd gear 2 qts. 8.2 miles maybe error of .2 18 mph hr. qt. 4.2 4th gear 4.8 30 -- qt. 3.6 all out 40. -- 3.2 4th gear 3.1 more power & jetter + faster engine obtainable. | ||