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).
Performance test graph comparing Standard and De-turbulated cylinder heads using a Delco ignition curve.
| Identifier | ExFiles\Box 101\3\ scan0016 | |
| Date | 9th June 1936 guessed | |
| DELCO IGNITION CURVE UPON WHICH PERFORMANCE TESTS WERE TAKEN TIMED AT 5° B.T.D.C. TABLE: STANDARD HEAD 10 - 20 M.P.H 3.53 SECS. 20 - 30 3.80 " 30 - 40 3.80 " 40 - 50 4.03 " 50 - 60 4.70 " 60 - 70 5.40 " TOTAL 25.26 DE-TURBULATED HEAD 3.73 SECS. 3.66 " 3.73 " 4.08 " 5.00 " 5.45 " TOTAL 25.65 BOTH CYL. HEADS 109 C.C'S AND 6.8:1 COMP. RATIO AXIS LABELS: Y-AXIS: ACTUAL FLYWHEEL IGN. ADVANCE X-AXIS: ENGINE R.P.M SIGNATURE: G M WYMAN | ||