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).
And comparing rear wheel arch clearances for the 25HP and J.3 models.
| Identifier | ExFiles\Box 178\3\ img076 | |
| Date | 20th February 1932 | |
| FROM IA/EV.{Ivan Evernden - coachwork} C. to US. ORIGINAL SECRET. IA/EV{Ivan Evernden - coachwork}2/M20.2.32. J.{Mr Johnson W.M.} 3. REAR WHEEL ARCH CLEARANCES. X 5830. We send herewith N. sch. 342y, showing the rear wheel arch clearances of the present 25HP. and J.{Mr Johnson W.M.} 3. compared., it being assumed that the axle on single wheel bump is thrown up pivoting about an axis formed by a straight line joining the eyes of the unbumped spring. We had drawn J.{Mr Johnson W.M.} 3. track at 58", and have not altered our drawing. We might therefore have increased the wheel arch width another .650", the track being 58.650", but on these experimental cars, and on the first reduction cars, we think a little extra clearance will be distinctly advantageous. We show clearances for both 18" and 19" rims. We are assuming the use of 18" rims and have made our wheel arch castings for these. IA/EV.{Ivan Evernden - coachwork} | ||