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).
Summary of technical specifications for American cars, covering tyres, brakes, suspension, and frames.
| Identifier | ExFiles\Box 128\3\ scan0066 | |
| Date | 1st February 1940 | |
| -5- (21) Tyres. The Packard 120 has 7.00 x 16 4-ply tyres. The Packard 6 and 120 tyre size is reduced from 6.50 x 16 to 6.25 x 16 (22) Brakes. Hydraulic brakes are now universal in America now that Wyllis have adopted them. Drums are of nickel chromium. The Buick Century brakes are 12 x 2 1/4", the biggest Buick 14 x 2". Pressed steel brake and clutch pedals are used on Packard and Chevrolet. (23) Road Suspension. Tension type shackles are being adopted. All Hudson rear springs are now 6" longer. La{L. A. Archer} Salle and Cadillac's are 54 1/2" long. Inside diameter of Buick coil springs have been increased to 5 1/2" permitting a shorter spring. On La{L. A. Archer} Salle and Cadillac 62 front suspension threaded shackles replace rubber bushings used on the lower control arm. (24) The frame cross member on all Chryslers has been reduced and the angle of the kick-up has been made sharper. Chevrolet frames have been revised in order to lower the floor. The side rails have been dropped 2 1/2" with lower front or rear axle kick ups. The frame back of the rear kick-up has been lowered 3" to provide deeper luggage space. Side rails are spread 2" further apart. (25) Direction signals have become popular. | ||