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).
Weight comparison table for vehicle components between Bentley, Pontiac, and Essex Terraplane models.
| Identifier | ExFiles\Box 21\6\ Scan215 | |
| Date | 8th March 1935 guessed | |
| COMPARISON OF BENTLEY & PONTIAC WEIGHTS. HEAVIER THAN PONTIAC. Section of Chassis. | % Heavier | Bentley | Pontiac | Diff. Brake Connections inc. equalisers, levers, pedals and linkage. | 401% | 82 | 16 | 66 Road Springs complete. | 67% | 117 | 70 | 47 Exhaust System | 213% | 63 | 20.2 | 42.8 Battery | 65% | 74 | 45 | 29 Radiator Complete with water Bentley latest 58 mm Matrix | 37% | 88 | 64 | 24 Rear Axle complete with Propellor Shaft | 9% | 236 | 217 | 19.7 Tool Kit Complete | 102% | 31.8 | 15.6 | 16.2 Petrol Tank empty. Both tanks assume 18 galls. | 34% | 48 | 34.5 | 13.5 Steering complete with Side Steering Tube | 31% | 41 | 31.3 | 9.7 Shock Absorbers & Control | 200% | 56 | 18.5 | 37.5 LIGHTER THAN PONTIAC. Front Axle Assembly complete | 50% | 119 | 234 | 115 Engine Unit & Gearbox | 12% | 683 | 775 | 92 Frame bare. Step Irons but no Brake Gear. | 21.8% | 194 | 248 | 54 5 Wheels & Tyres | 2.5% | 257 | 264 | 7 Bonnet | 14% | 44 | 51 | 7 COMPARISON OF BENTLEY & ESSEX TERRAPLANE WEIGHTS. HEAVIER THAN ESSEX. Section of Chassis | % Heavier | Bentley | Essex | Diffnce. Brake Transmission | 372% | 83 | 16.4 | 67 Road Springs Complete | 14.7% | 117 | 102 | 15 Exhaust System | 284.8% | 63 | 16.5 | 47 Battery | 54% | 74 | 48 | 26 Rear Axle complete with Propellor Shaft | 46.5% | 236 | 161 | 75 Tool Kit Complete | 138% | 31 | 13 | 18 Petrol Tank. (different capacity allowed for). | 71.4% | 48 | 28 | 20 Steering Complete with Side Steering Tube. | 46.4% | 41 | 28 | 13 Shock Absorbers & Control | 203.5% | 56 | 15.8 | 40.2 Front axle Assembly complete | 14.4% | 119 | 104 | 15 Engine & Gearbox | 21.3% | 683 | 563 | 120 Bonnet | 16% | 44 | 38 | 6 Wheels & Tyres | 25% | 257 | 207 | 50 LIGHTER THAN ESSEX. Frame | 22.4% | 194 | 250 | 56 Radiator (no water) Bentley latest 58 mm. Matrix. | 8% | 74.4 | 81 | 6.6 Nett amount by which Essex is lighter than the Bentley is 413.6 lbs. on the chassis. Body and wings 159 lbs. heavier. | ||