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).
Power curve comparison between a long duration camshaft and a standard camshaft for an FXI engine.
| Identifier | ExFiles\Box 33\4\ Scan123 | |
| Date | 12th October 1928 | |
| POWER CURVE WITH LONG DURṆ CAMSHAFT. COMPARISON WITH STANDARD CAMSHAFT. ROLLS ROYCE FXI ENGINE N° SLA. T49. COMPRESSION RATIO = 7:1 GEAR RATIO = .552. MAGNETO TIMING = 40° BEFORE T.D.C. FUEL USED = T.E.L. DATE OF TEST 9/10-10-28. CURVES CORRECTED TO N.T.P. BRAKE HORSE POWER. SP.{Mr Spinney} CONS. (PTS/BHP/HR). RPM OF ENGINE. LONG DURATION CAMSHAFT. STANDARD CAMSHAFT. SPECIFIC CONSUMPTION. VALVE TIMINGS (.020 TAPPET CLEARANCE) | | LONG DURṆ CAMSHAFT | STD. CAMSHAFT | |---|---|---| | INLET OPENS | 12½° BEFORE TDC | 8° AFTER TDC | | INLET CLOSES | 46° AFTER BDC | 46° AFTER BDC | | EXHAUST OPENS | 51° BEFORE BDC | 38° BEFORE BDC | | EXHAUST CLOSES | 5° AFTER TDC | 13° AFTER TDC | Handwritten Signature: A.J.Sillius Handwritten Date: 13-10-28 | ||