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).
Road test comparison of old versus new experimental piston rings focusing on fuel and oil consumption.
| Identifier | ExFiles\Box 1\8\ B001_X100 Engine Chassis-page254 | |
| Date | 1st April 1933 | |
| Rm.{William Robotham - Chief Engineer} from F.Dodd. X4027a. 1.4.33. 3.PER.II. Comparative consumption figures taken with old and new type Expl. piston rings. Old type scraper rings to E.100037. 2.683" Dia. Gas ring to E.100036. 2.725" New Expl. scraper ring to Hs.{Lord Ernest Hives - Chair}945 .015 chamfer on the scraper ring the groove being shallower to increase the unit pressure. .015 CHAM. AT 45º 2.705" Dia Gas ring to Hs.{Lord Ernest Hives - Chair}949. 2.715" 2.725" ROAD TEST FIGURES. Mileage 170.5. Average speed 42.5 mph. Petrol used 11 galls. Petrol Cons. 15.45 mpg. Oil Used 3.3 pts. Cons. 413 mpg. ROAD TEST FIGURES. 1st 2nd ROAD TEST 176 42 2.25 Pts 625.6 Mileage 182. Average speed 42 mph. Petrol used 11.5 galls. Petrol cons. 15.84 mpg. Oil used 3.5 pts. Oil cons. 416 mpg. ----------- F.Dodd. | ||