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).
Engine fuel consumption and a comparative test of different spark plug types.
| Identifier | ExFiles\Box 36\2\ scan 160 | |
| Date | 9th March 1928 guessed | |
| contd :- -2- was observed towards the end of the run; Petrol consumption averaged .46 pts/HP/hr. and oil consumption 5 pts/hr. air temp. 10°C. SPARKING PLUGS. For the above tests one side of the engine was fitted with Lodge A-30 plugs and the remaining block with Champion R.11 as a basis for comparison. There was no difference in the behaviour of each half set of plugs during any of the tests and all were in good condition at the end of the endurance run. Comparative tests were also made at full throttle using 20/80 mixture and : (1) Champion R.11 plugs. (2) Lodge A-30 " (3) KLG.541 " There was no difference in the performance of the engine on each of these plugs and in each case the engine was braked down to 1900 r.p.m. on full throttle without pre-ignition setting in. Full throttle with silencers fitted, detonations became audible at 2100 r.p.m. (514 B.HP. = 150 lbs/sq.in. BMEP.) and increased in severity down to 1900 r.p.m. accompanied by a falling off in BMEP. Under throttling conditions it must be noted that power and BMEP. falls off more rapidly than the peak (explosion) pressures so that even when the compression ratio is not altered, mean effective pressure is not a true measure of any liability to detonate. Hs{Lord Ernest Hives - Chair}/V.Halliwell. | ||