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).
Wheel, tyre, spring, and clearance specifications for a car.
| Identifier | ExFiles\Box 123\3\ scan0021 | |
| Date | 8th August 1933 | |
| To Ev.{Ivan Evernden - coachwork} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} C. E.{Mr Elliott - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} C. C. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} 8/KT. 8. 8.33. F.2. J.3. With reference to Ev.{Ivan Evernden - coachwork}1/IH.4.8.33. (1) We are proposing to use 6" x 18" wheels and tyres on this car which have a rolling circumference of 92". In the laden position the road springs will have 2.250" buffer clearance on the front and 4" buffer clearance on the rear. This is equal to an initial deflection of almost 5" on the front and 6.250" on the rear. (2) With reference to the floor, we know no reason why this should not be 2" above the chassis frame. (3) We want some design work doing on this point. At present we cannot tell you anything about it. (4) There is little doubt that the ground clearance with the J.3. pressed steel crossmember will have to be raised 1.5" in order to be reasonable. Here again some design work is required. We cannot efficiently increase the free camber of the spring by this amount, the crossmember being lower than the other parts in the vicinity by about .5". (5) We understand that E.{Mr Elliott - Chief Engineer} is working on this point. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||