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).
Difficulties with torque reaction in a sports car and the effects of different engine setups.
| Identifier | ExFiles\Box 65\4\ scan0074 | |
| Date | 30th January 1928 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c.c. to BJ. WOP. c.c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c.c. to BY.{R.W. Bailey - Chief Engineer} OY. 48005 Hs{Lord Ernest Hives - Chair}/Rml/LG30.1.28. TORQUE REACTION. The most noticeable difficulty that we have encountered on the sports car is that of torque reaction. The observations we have to offer on this phenomenon so far are as follows :- (a) Long duration camshaft. Up to a certain M.E.P. torque reaction is not very obstrusive. If we further increase the M.E.P. even a little above this point we are in trouble. Thus with the long duration camshaft and 5/1 compression ratio the torque reaction is no worse than on a standard car. If we use the standard camshaft under these circumstances a periodic vibration on the pick up is at once apparent though we have only increased the low speed M.E.P. by a few pounds. (b) Rubber flexibility. in the engine mounting, while excellent for high speed vibrations, increases torque reaction vibrations unless this flexibility is kept down to the absolute minimum. We have been trying rubber of varying rating and with varying strength, as soon as we increase the flexibility in the mounting, pick up vibrations increase. (c) Solid engine mounting in front and rubber mounting behind does not help us very much with the present frame. The vibration is transferred to the front wings but is also transmitted to the driving seats. High speed vibrations also start to give trouble owing to the increased rigidity of the engine mounting. contd:- | ||