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).
Suspension softness, spring ratings for the 40/50 model, and a request for information on Hofmann air springs.
| Identifier | ExFiles\Box 43\2\ Scan194 | |
| Date | 26th January 1927 | |
| Oy1-E-12627 -3- January 26, 1927. (3) softness in the suspension was the one thing that we could always have plenty of. But your article makes me think that they may have advantages. Shall we get you a set? They have been installed in R.R.cars, but I haven't seen them. (4) Spring Ratings (p.24). The 40/50 rear spring F-10612 is given as having a rating of 125 lbs. per inch at the rear for a 2000 lb. spring. Reference to print F-10612 shows that this spring is rated at 1/2" neg. camber or 3" total deflection at the centre. Rating at the centre is thus 2000/3 or 667 lbs.per inch, and at the rear 167 lbs.per inch. Although we set up our springs 1/2" more we rate them flat, so that our 2000 lb. spring has the same rating. A rear rating of 125 lbs./in. applies to a 1500 lb. spring. Please let me know about the Hofmann air springs. I would welcome your other comments, (particularly if you swing a 20 hp. and find the M.I. of its unsprung mass). Yours very truly, Maurice Olley MO/E [handwritten note in margin: to copy] | ||