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).
Four engine performance comparison graphs for Wraith, Ripple, Corniche, and Phantom III models.
| Identifier | ExFiles\Box 124\2\ scan0303 | |
| Date | 1st December 1938 | |
| WRAITH W.III Nº 8 B.H.P. B.M.E.P. R.P.M. CYL. HEAD EW 1922 (130 cc's) C/R = 6:1 CAMSHAFT VALVE TIMING @ .025. I.O. 6° AT. EO 42° BB. I.C. 44° AB. EC 5° BT.{Capt. J. S. Burt - Engineer} INDN. SYSTEM STROMBERG D.C. 42 CARB. ON 1.6 BORE PIPE. PISTONS R.R SPLIT. EW 1967. ① OPEN EXHAUST ② STD. WRAITH EXH SYSTEM ③ NON-DETN AS ② RIPPLE R Nº 2 B.H.P. B.M.E.P. R.P.M. CYL. HEAD EW. 1922 (35cc's) C/R = 6.3:1. CAMSHAFT VALVE TIMING @ I.O. T.O.C. EO. 42° BB I.C. 42° AB. EC. 0° AT. INDN. SYSTEM STROMBERG DC 42 CARB. ON 1.600 BORE PIPE PISTONS EW 2170 RR SPLIT .360 BUMP (MADE BY AEROLITE) ① OPEN EXHAUST ② B II EXH. SYSTEM ③ NON. DETN. AS ② CORNICHE W.III. Nº 10 B.H.P. B.M.E.P. R.P.M. CYL. HEAD EW 1922 (130 cc's) C/R = 7.45 : 1 CAMSHAFT VALVE TIMING @ .030 CLCE. I.O. 1.5° AT. E.O. 40° BB I.C. 46° AB. E.C. 6° AT. INDN. SYSTEM. 2. H.C. S.U. CARBS. ON 1.750" PIPE. PISTONS P. 452 A.{Mr Adams} AEROLITE (.330 BUMP). ① OPEN EXHAUST. ② SPECIAL CHASSIS EXH. SYSTEM. ③ NON.DETN. AS ② (REDLINE) ④ B.V NON.DETN.(BII EXH. SYSTEM)(REDLINE) PHANTOM III POWER COMPARISON BETWEEN STANDARD AND CONTINENTAL UNIT. UNITS WITH SAME WATER HEAT HOT SPOT. (STD). CURVES WITH STD. CARBS. (STROMBERG). OPEN EXHAUST STD. 6 PORT HEAD VALVES INLET 1.450 DIA. EXHAUST 1.250 DIA. 4 PORT HEAD VALVES INLET 1.500 DIA. EXHAUST 1.300 DIA. ① STD. 6 PORT HEAD } 6:1 STD. C/R ② ---⚬---⚬--- 4 PORT HEAD VALVE TIMING @ .020" TAPPET CLEARANCE STANDARD CAMSHAFT. I.O. 7° ATDC. E.O. 47° BBDC. I.C. 42° ABDC. E.C. 8° BTDC. ①A B.H.P. WITH COMPLETE STD. EXHAUST SYSTEM FITTED. OTHERWISE AS TEST ① ③ -x--x- "CONTINENTAL" 4 PORT HEAD DETURBULATED. 6.5:1 C/R.{Sir Henry Royce} CAMSHAFT WITH LONG TOES. AUTO. TAPPETS DELETED. VALVE TIMING @ .020" TAPPET CLEARANCE EX 23243 CAMSHAFT. I.O. 1° BTDC E.O. 40° BBDC. I.C. 48° ABDC E.C. 0° BTDC. | ||