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).
Comparing the performance of standard versus stiffer road springs under various load conditions.
| Identifier | ExFiles\Box 19\1\ Scan209 | |
| Date | 16th June 1932 | |
| Hd{Mr Hayward/Mr Huddy}/SB.{Mr Bull/Mr Bannister} From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c.c. to EV.{Ivan Evernden - coachwork} c.c. to EP.{G. Eric Platford - Chief Quality Engineer} c.c. to EX. c.c. to MS. 87120 17410 Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson}1/MA.16. 6. 32. Re. STIFFER ROAD SPRINGS P.II. Referring to Hd{Mr Hayward/Mr Huddy}/SB.{Mr Bull/Mr Bannister}10/Kh.7.6.32. The comparison made is not fair because it assumes that a car would have 1350 lb springs fitted if spring normally and 1250 if spring continentally which is incorrect. Taking the car in each case with 1350 lbs springs we get :- Standard. Stiffer. Poundage 1350 1350 Rate 164lbs/1" 280lbs/1" Buffer Clce. 3.600 2.520 Increase in static load to buffers 590 555 However, our experience is that "crashing" occurs when the buffer is compressed 1" and the driver does not know when the axle "flicks" the buffers. The continental springs were designed on this assumption, and the "crashing" point taken as 4.850 neg camber. The relative immunity from crashing then becomes :- Standard. Stiffer. Rate 164lbs/1" 221lbs/1" Deflection from normal riding to "crashing" 4.8 3.750 Increase in "static" load to produce this result 790 lbs 820 lbs | ||