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).
Graph comparing the maximum ignition advance to avoid detonation for a cylinder head before and after modification.
| Identifier | ExFiles\Box 86\1\ scan0142 | |
| Date | 2nd March 1935 | |
| COMPARISON OF CYLINDER HEADS B.V.79 UNIT:- B2 SPECIFICATION:- R.H.C./C.P. 7/E.P. 31-1-35 FULL LINE REPRESENTS CYL. HEAD LEC 3562 BEFORE MODIFICATION DOTTED LINE " " " AFTER MODIFICATION Ex16041 ALL OTHER PARTICULARS SEE CURVE B.V.78 MAXIMUM IGNITION ADVANCE AVOIDING DETONATION. IGNITION ADVANCE (DEGREES BEFORE T.D.C.) R.P.M. R.H/A 2.3.35 | ||