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).
Table comparing the weight differences and subsequent advantages of a 4¼-Litre Bentley over a Jaguar.
| Identifier | ExFiles\Box 126\5\ scan0090 | |
| Date | 16th September 1938 guessed | |
| COMPARISON OF JAGUAR WITH 4¼-LITRE BENTLEY. Item. Amount heavier than corresponding Jaguar part. Advantage gained from increased weight. BODY 17 lbs. SILENT BODY MOUNTING. REAR ROAD SPRINGS 25 lbs. DURABILITY. BRAKES 16 lbs. SERVO OPERATION. ENGINE 35 lbs. GREATER BEARING AREA. HEAVIER FLYWHEEL GIVES BETTER SLOW RUNNING. PETROL SYSTEM & PETROL 35 lbs. 4 GALLS. MORE PETROL CARRIED. SIDE CHANGE SPEED LEVERS. 5 lbs. CENTRAL CHANGE NOT ACCEPTABLE. ONE SHOT CHASSIS LUBRICATION. 18 lbs. 12 oz. MARKED CONVENIENCE FOR CUSTOMER. DAMPER GOVERNOR CONTROL. 9 lbs. 2 oz. RIDING REFINEMENT. 160 lbs. 14 oz. | ||