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 results for a 27 Ex. car at Brooklands, including an acceleration graph and valve timing diagram.
| Identifier | ExFiles\Box 19\1\ Scan128 | |
| Date | 5th October 1931 | |
| 27 Ex. CAR. PERFORMANCE TESTS ON BROOKLANDS. 5TH OCT. 1931 Le.C. 2905/6 R.R. TWIN CHOKE CARBURETTER. (MODIFIED TO CURE FLOODING ON CORNERS) WITH AIR SILENCER (EXPTL.) 114° W.W CAMSHAFT (E.82448) COMPRESSION RATIO 4.8:1 REAR AXLE RATIO STANDARD (3.727:1) CAR WEIGHT COMPLETE 46 CWT. 2 QRS. 21" RACING TYRES. (EFFECTIVE CIRCUMFERENCE AT 50LBS/D") PRESSURE 105.75" = 599 REVS/MILE. ENGINE REVS/MIN AT 60 M.P.H. TOP GEAR = 2233 ALL RESULTS WITH CUT-OUT OPEN BEST LAP SPEED 87.1 M.P.H. HALF MILE 89.11 M.P.H. } AGAINST STRONG HEAD WIND. MILE 87.38 M.P.H. } VALVE TIMING .013" CL'NCE I.O. 10.2° E.C. 12.7° E.O. 56.8° I.C. 53.7° B.D.C. ACCELERATION. TOP GEAR. ROAD SPEED (M.P.H.) TIME (SECS.) | ||