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 and valve gear for a sports chassis.
| Identifier | WestWitteringFiles\Q\July1927-September1927\ Scan152 | |
| Date | 24th September 1927 | |
| FROM E.{Mr Elliott - Chief Engineer} C. to HS.{Lord Ernest Hives - Chair} PHANTOM CYL. BLOCK AND VALVE GEAR FOR SPORTS CHASSIS. √3050 X8060 X8774 We send herewith LeC. 2464. shewing the above. You will require a new camshaft and new cam forms to suit the rollerless tappets shewn. The drawing has been dimensioned up with a view to squaring up the tappet and push rod gear so that it is parallel from top to bottom at the centres of the existing rockers. At the same time larger tubes are provided for the passage of the push rods through the cyl. head. These larger tubes are similar in diameter to the eccentric ones recently sent through, but are now concentric with the push rods. The rocker position shewn is like the present standard. If it is finally concluded that valve seat taps can be eliminated by raising the rocker centre relative to the top of the valve, and we adopt this modification, it will improve the geometry of the push rod end of the rocker, and reduce the side movement of the push rod. This drawing shews a small modification required on the head. At the same time a new copper asbestos gasket will have to be used to suit the changes in the valve gear and the waterways. Designs will be sent through later for the revised con. rod and piston. In the meantime we should be glad if you could rescheme the carrier wheel in the wheelcase to suit a crankchamber 9 1/2" high instead of 11". The carrier wheel should be placed below the pair of gears with which it engages, instead of above, and its centre will come somewhere over the centre of the oil gallery pipe in the crankchamber. We are not sure at the moment whether it will be necessary to move the centre of the dynamo drive to get enough room for the oil pump drive; we hope this will not be necessary but will let you know as early as possible. E.{Mr Elliott - Chief Engineer} | ||