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).
Three indicator diagrams showing performance of a 2-stroke low-pressure system at various temperatures and RPMs.
| Identifier | ExFiles\Box 179b\2\ img098 | |
| Date | 18th October 1932 guessed | |
| Top Left Graph: 90/90 LB. 2" STROKE. LOW PRESS COLD-25°C ONE ATMOSPHERIC INLET TO 'HAT'. .250" HAT. .005 CLEARANCE R.P.M 360 260 180 90 Y-Axis: 308 LB/[] X-Axis: 120 1.5 Graph no: 7 Top Right Graph: 90/90 LB. 2" STROKE. LOW PRESS 60°C ONE ATMOSPHERIC INLET TO 'HAT' R.P.M 360 260 180 90 Y-Axis: 308 LBS/[] Graph no: 8 Bottom Left Graph: 90/90 LB. 2" STROKE LOW PRESS. AFTER RE-COOLING ONE ATMOSPHERIC INLET TO "HAT. B.P. LOAD. 140 LB. DROPPING TO 110 LB R.P.M 360 260 180 90 Y-Axis: 308 LBS/[] Graph no: 9 | ||