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).
400-mile test run of chassis 1.E.X, detailing performance, fuel consumption, and vibration issues.
| Identifier | Morton\M22\ img044 | |
| Date | 28th July 1919 | |
| X 3058 Bn{W.O. Bentley / Mr Barrington} - 400 MILE TEST RUN ON 1 EX. Bn{W.O. Bentley / Mr Barrington}5/W28.7.19. contd. Chassis 1.E.X -6- Consumption. with the water boiling. With so much boiling the top of the radiator got very dirty with the rusty water, as the cap did not appear to be very tight. Also the front springs and undershield suffer in the same way from the overflow pipe. This latter could with benefit be moved to blow straight on to the road. Although this engine is reasonably smooth at high speeds when one bears in mind the good H.P. obtained, yet it does not compare with the engine in 49-GB., as regards this point. I do not think 49-GB has less power and I understand that the compression is higher than in 1.E.X. We are investigating this point further. Also there was a bad vibration between 24 1/2 and 25 1/2 miles per hour, which could be felt on the pedals and steering column and made some considerable noise with the dash board and fittings.* This has since been almost entirely cured by reducing slightly the load on the springs on the slipper fly-wheel. We still suffer slightly from missing, when on the magento alone, when picking up from low speeds at full throttle, and I notice this persists when the magneto ignites from plugs over the inlet. This is a point which requires further investigation - it is not entirely cured by running rich. Over the whole of the run I averaged 14.25 miles per gallon, and the first four hundred odd miles fifteen miles per gallon. The whole run of course included a lot of hill climbing in Devonshire and Cornwall, and on the whole fairly fast running together with some pottering in towns and villages. I think this consumption is reasonably good. I usually ran two notches weak and for more than half the distance of course, on magneto alone and with the inlet valve position of plug. * Scuttle shake or shimming Contd. [Upside down text at bottom right] R.R. 235A (500 T) (S.D. 408. 26-4-17. Bm) 2/156/15. | ||