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 tests for the 1.EX car, comparing different axle and compression configurations.
| Identifier | ExFiles\Box 29\3\ Scan109 | |
| Date | 16th September 1922 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. and BJ. c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to EY. X788 hs{Lord Ernest Hives - Chair}3/LG16.9.22. X788 X3763 CONSUMPTION TESTS TAKEN ON 1.EX CAR. Comparative tests were taken on this car over the same roads and under the same conditions comparing the 14/15 tooth axles. The car was driven normally and the carburetter adjusted to obtain the minimum consumption. The tests show that with a 15-tooth axle high compression (23¾) the consumption was 15½ miles to the gallon - with a 14-tooth axle the consumption was 14½ miles to the gallon Tests taken on 1.EX Car with a 15-tooth axle with high compression (23 cu.ins.) and medium compression (26 cu.ins. otherwise similar conditions, the miles per gallon with high compression (23¾) was 16 M.P.G. - with the medium compression (26) it was 15 M.P.G. We consider from the average of all our tests that the present standard medium compression car fitted with a 14-tooth axle will consume approximately 7/8% more petrol than the high compression (23¾) fitted with a 15-tooth axle. Hs.{Lord Ernest Hives - Chair} | ||