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).
10,000-mile test car to determine the optimal ignition timing on Ticknall Hill.
| Identifier | ExFiles\Box 51\5\ Scan256 | |
| Date | 26th October 1931 | |
| FILES. X5681 26.10.31. x5840. x6129 x5681 18.G.IV. 10,000 miles Test Car. The following test was carried out to determine the latest ignition setting that could be used without loss of power. It will be seen that 10° B.T.D.C. appears to be the optimum timing. Taken on Ticknall Hill. Figures are average of three tests each. Full advance = 13° B.T.D.C. at 63.1 secs. 4 notches retard = 11° " " 62.9 " 6 " " = 9° " " 63.4 " 8 " " = 7° " " 64.2 " Watford Speedometer checked at 50 m.p.h. Time = 75 seconds, therefore 4% fast. 5.7 c/r. camshaft to By {R.W. Bailey - Chief Engineer} /CS.2/MH {M. Huckerby} 22.9.31. Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} | ||