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).
Letter from Maurice Olley to Mr. Grylls discussing the effects of traction, load, and braking on tyre cornering power and oversteer.
| Identifier | ExFiles\Box 170\3\ img141 | |
| Date | 29th December 1937 | |
| Mr. Grylls, Rolls Royce Limited, Derby. 29. 12. 37. slightly more towards oversteer because increased traction in the rear tyres reduces their cornering power appreciably. Driving slow in a high lane reverses conditions but it is a thing we have'nt bothered with. The additional centrifugal load on the tyres is probably a slight help at the higher slip angles because at such angles side thrust does increase with load up to about 150% of the rated load. However since the effect is distributed to front and rear it will act like a general increase of tyre pressure and will change both front and rear slip angles, but will not change the steering angle much. Apparently we have got to say that both traction and braking (i.e. anything which interferes with the free rolling of the wheel) decrease cornering power. Therefore increased traction tends towards increased oversteer. Best Wishes for 1938. Yours, Maurice Olley Maurice Olley. | ||