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).
Comparison of the number of parts in B.V. and Vauxhall gearboxes.
| Identifier | ExFiles\Box 148\2\ scan0166 | |
| Date | 27th April 1939 | |
| DA. {Bernard Day - Chassis Design} 1/G.27.4.39. NOS. OF PARTS B.V. AND VAUXHALL GEARBOXES. | B.V. 4 SPEEDS THREE SYNCHRONISED HELICAL 1ST. & R. {Sir Henry Royce} | TOTAL | K.PARTS STUDS,NUTS & WASHERS. | NON-STANDARD. DIFFERENCE. | |---|---|---|---| | Gearbox and Actuating Gear. 80 steel balls counted as one. | 270 | 204 | 66 | | 1st. & 3rd. Motion Shaft. | 42 | 0 | 42 | | 2nd. Motion Shaft. | 12 | 0 | 12 | | Reverse Shaft. | 5 | 2 | 3 | | Vauxhall Central Gear Lever. | 7 | 0 | 7 | | Vauxhall Speedo Drive. | 8 | 4 | 4 | | TOTALS. | 344 | 210 | 134 | | 25 HP. Vauxhall 4 Speeds two synchronised Straight tooth 1st, 2nd and Reverse. | 146 | 43 | 103 | B.V. actuating gear provides for either overdrive or standard rates with only two different pieces. A comparison with the current 25 HP. Vauxhall, 3 Speed box is less favourable than for the 4 speed. | ||