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).
Performance of longer connecting rods and lighter pistons in the 46-PK engine.
| Identifier | ExFiles\Box 65\4\ scan0262 | |
| Date | 12th July 1924 | |
| To CJ. from R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} Rg.{Mr Rowledge} Hs.{Lord Ernest Hives - Chair} Da.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} BY.{R.W. Bailey - Chief Engineer} PN.{Mr Northey} H.{Arthur M. Hanbury - Head Complaints} EP.{G. Eric Platford - Chief Quality Engineer} C. X8030 S E C R E T. R2/M12.7.24. EAC.11. RE. 46-PK. RE. PISTONS AND CON. RODS. X.9030 (crossed out) X.9040 (crossed out) X8030 X9040 The engine of 46-PK was fitted with longer con. rods, and lighter pistons, and was very smooth indeed on the road under all conditions. We are informed however by Mr. Hives that there is another EAC. engine in Derby equally smooth, but having the original shorter length of rods. The advantage of the longer rods is difficult to appreciate as we expected from calculation, and I therefore think we shall do best by reducing the weight of the moving parts rather than altering the dimensions of the engine. Let us therefore leave the crankcase unaltered, but fit the shorter pistons shewn on LeC.1879., with rods only .5" longer to suit, and reduce the scantlings of these parts as much as possible. The recent work on exhaust pipe, induction pipes, and throttle governor, recently sent through, will require slight modification to suit this slight change of policy. R.{Sir Henry Royce} | ||