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).
Modifications to the Phantom cylinder block to reduce distortion and eliminate piston knock.
| Identifier | ExFiles\Box 48\1\ Scan191 | |
| Date | 1st August 1927 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/ACL. c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to BY.{R.W. Bailey - Chief Engineer} OY. c. to DA.{Bernard Day - Chassis Design} V4190 Hs{Lord Ernest Hives - Chair}/ACL2/LG26. 8. 27. MODIFICATIONS TO REDUCE PHANTOM CYLINDER BLOCK DISTORTION. X.8050 The modification to the Phantom cyl. block - sch.951 - which consists of vertical webs or struts near the holding down bolts and also webs under the jacket cover plate on the steering side, have proved to be very effective in reducing the distortion of the cyl. skirts when under tension of the holding down bolts. It will be remembered that cyl. skirt distortion resulted in one of the piston knock troubles which was nearly always evident in cyls. Nos. 2 and 5. Previous to the modification it was found the skirts of Nos. 2 and 5 cyls. considerably increased in dia. between the pressure and non-pressure sides when tightened down on the crankcase which resulted in the piston changing over an audible knock at bottom centre. This modification appears to afford the solution to the above piston knock trouble and very satisfactory results have been obtained by the Test Dept. since fitting the latest cylinders. Hs{Lord Ernest Hives - Chair}/A.C.Lovesey. | ||