Performance graphs for a J.III rear component showing the effects of different valve configurations under low pressure.
| Identifier | ExFiles\Box 151\2\ scan0065 | |
| Date | 11th April 1933 guessed | |
| Top Graph: J. {Mr Johnson W.M.} III REAR. 35/35 LB. LOW PRESSURE BLANK DISC VALVE IN EXT. PRESS INLET 4" STROKE 5-4-33 308 LB/D" = 133 LB. 120" I.S. R.P.M. 180 135 90 45 GOV. PRESS. 4 LB/D" 45 R.P.M - 0 LB/D" AFTER ABOVE TESTS. 45 R.P.M. - 0 LB/D" BEFORE ABOVE TESTS. Middle Graph: J. {Mr Johnson W.M.} III REAR. 35/35 LB. LOW PRESSURE .250" EXT. PRESS INLET VALVE - 1 OFF .062" DIA. RELEASE VENT. 4" STROKE 6-3-33 308 LB/D" = 133 LB. 120" I.S. R.P.M. 180 135 90 45 GOV. PRESS 4 LB/D" 45 R.P.M. - 0 LB/D" BEFORE ABOVE TESTS. AFTER TESTS. Bottom Graph: RD J. {Mr Johnson W.M.} III REAR. 35/35 LB. LOW PRESSURE DISC VALVE DRILLED .015" IN EXT. PRESS INLET. 4" STROKE 6-4-33 308 LB/D" = 133 LB. 120" I.S. R.P.M. 180 135 90 45 GOV. PRESS 4 LB/D" 45 R.P.M. - 0 LB/D" BEFORE & AFTER ABOVE TESTS. | ||
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).