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).
Data comparison table for flywheels used on various 6 and 8 cylinder engines.
| Identifier | ExFiles\Box 124\2\ scan0048 | |
| Date | 1st January 1950 | |
| FLYWHEEL DATA - 6 CYLINDER ALUMINIUM - B.60 AND B.80 ENGINES AND R.R. STARTER MOTOR. TABLE DATA: COLUMN 1: ENGINE: ALUM - 6 CYL. CLUTCH: 11" LONG OR B.B INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1580 CLUTCH INERTIA COMPLETE: 450 TOTAL INERTIA: 2030 % INERTIA RATIO 11" CLUTCH: 100% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 51 LBS. % WEIGHT RATIO 11" CLUTCH: 100% CAR USED ON: STANDARD PRODUCTION REMARKS: RIGID FLYWHEEL FOR BASIS OF COMPARISON. COLUMN 2: ENGINE: ALUM - 6 CYL. CLUTCH: 10" INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1580 CLUTCH INERTIA COMPLETE: 250 TOTAL INERTIA: 1830 % INERTIA RATIO 10" CLUTCH: 100% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 51 LBS. % WEIGHT RATIO 10" CLUTCH: 100% COLUMN 3: ENGINE: C.I. - 8 CYL CLUTCH: 11" LONG PART NUMBERS: RM.{William Robotham - Chief Engineer}576 or G.B.5290, RM.{William Robotham - Chief Engineer}574 or G.B.5292, RM.{William Robotham - Chief Engineer}575 G.B.5291 INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1628 CLUTCH INERTIA COMPLETE: 450 TOTAL INERTIA: 2078 % INERTIA RATIO 11" CLUTCH: 105% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 43 LBS. % WEIGHT RATIO 11" CLUTCH: 84% CAR USED ON: 11-B-5, 30-G-7, 33-G-7, 4-B-50. REMARKS: R.R. STARTER MOTOR COLUMN 4: ENGINE: ALUM-6CYL STD CLUTCH: 10" LONG PART NUMBERS: RM.{William Robotham - Chief Engineer}569 G.B.4758., G.B.5013, G.B.5293 INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1470 CLUTCH INERTIA COMPLETE: 250 TOTAL INERTIA: 1720 % INERTIA RATIO 10" CLUTCH: 94% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 43.5 LBS. % WEIGHT RATIO 10" CLUTCH: 85% CAR USED ON: 6-B-5, 7-B-5, 8-B-5. REMARKS: B-5 STANDARD R.R. STARTER COLUMN 5: ENGINE: ALUM-6CYL LT CLUTCH: 10" LONG PART NUMBERS: RM.{William Robotham - Chief Engineer}570 G.B.5206., G.B.5013, G.B.5293 INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1088 CLUTCH INERTIA COMPLETE: 250 TOTAL INERTIA: 1338 % INERTIA RATIO 10" CLUTCH: 73% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 32.4 LBS. % WEIGHT RATIO 10" CLUTCH: 64% CAR USED ON: 14-B-5. REMARKS: "CORNICHE" R.R. STARTER COLUMN 6: ENGINE: C.I.-6CYL STD CLUTCH: 10" LONG PART NUMBERS: G.B.4918, G.B.5013, G.B.5293 INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1477 CLUTCH INERTIA COMPLETE: 250 TOTAL INERTIA: 1727 % INERTIA RATIO 10" CLUTCH: 94% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 39.5 LBS. % WEIGHT RATIO 10" CLUTCH: 68% CAR USED ON: 3-B-50. REMARKS: HEAVY R.R. STARTER COLUMN 7: ENGINE: C.I.-6CYL LT CLUTCH: 10" LONG PART NUMBERS: RM.{William Robotham - Chief Engineer}572., G.B.5013, G.B.5293 INERTIA-LBS.INS² OF COMPLETE FLYWHEEL: 1088 CLUTCH INERTIA COMPLETE: 250 TOTAL INERTIA: 1338 % INERTIA RATIO 10" CLUTCH: 73% WEIGHT OF FLYWHEEL COMPLETE-WITHOUT CLUTCH: 31.4 LBS. % WEIGHT RATIO 10" CLUTCH: 62% REMARKS: LIGHT R.R. STARTER | ||