Table of actual valve timing data taken on an engine with .020 tappet clearance, showing results from twin carburetor tests.
| Identifier | ExFiles\Box 6\7\ 07-page093 | |
| Date | 10th January 1932 | |
| ACTUAL VALVE TIMING TAKEN ON ENGINE WITH .020 TAPPET CLCE. CAMSHAFT | 116° | 112° | 110° IN. OPENS | 13° A.T.C. | 7° A.T.C. | 16° A.T.C. IN. CLOSES | 49° A.B.C. | 43° A.B.C. | 37° A.B.C. EX. OPENS | 42° B.B.C. | 43° B.B.C. | 28° B.B.C. EX. CLOSES | 2° A.T.C. | 5° A.T.C. | 4° A.T.C. ABOVE ARE THE BEST TIMINGS FOUND DURING TWIN CARB TESTS ON 'JAPAX'. 10/1/32 | ||
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).