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).
Specifications for the J.3. project covering the layout of the frame, transmission, and springs.
| Identifier | ExFiles\Box 106\1\ scan0286 | |
| Date | 9th July 1931 | |
| X5410 BY.{R.W. Bailey - Chief Engineer} FROM DA.{Bernard Day - Chassis Design} C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} DA{Bernard Day - Chassis Design}1/M7.9.31. J.3. - LAYOUT OF FRAME TRANSMISSION, & SPRINGS. X. 5380 X. 5410 X. 5430 X. 5340 X. 5350 We send herewith N.sch.3335. shewing the frame, transmission C/L. position of engine, steering column positions and road springs for J.{Mr Johnson W.M.} 3. FRAME. This drawing gives enough information to enable you to order a frame, which we anticipate will be cold pressed. The diameters of cross tubes are indicated, but subsequent designs will be sent for these. The frame should be bought with ample length to spare at its ends. SPRINGS. Sufficient information is given to enable you to get out and order front and rear springs for the first car which will be a maximumbodied 6 seater. Should any extra depth beyond the 2.350" be required for the front springs this can be obtained by raising the front of the car, or we may drop the front axle up to .500". The rear springs are the same as standard but have 1.5" of negative camber under full load. The front axle is that of N.sch. 3246-7. originally done for J+3., but modifications have to be sent to you for the steering levers, hubs and brakes. The rear end of the front spring is to N. sch. 3207. In each case one eye of the front spring is rolled. STEERING COLUMN. The steering positions are those now standard. PROPELLER SHAFT. Since this shaft is reduced in length from 58.900" we estimate that a 2.5" dia. shaft will be adequate from the point of view of whirling. The present ends are used. This is all the information you need for this section. REAR AXLE. You have already received the design of the rear axle centre box for .850 offset hypoid gears. DA.{Bernard Day - Chassis Design} | ||