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 and issues with a Ripplet Intermediate Type Cylinder Head.
| Identifier | ExFiles\Box 118\1\ scan0013 | |
| Date | 10th January 1940 | |
| To Rm.{William Robotham - Chief Engineer} c. Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation} c. HPS{Horace Percy Smith - Experimental Factory Mgr}/RH.{R. Hollingworth} JNR.{Charles L. Jenner}1/BA.10.1.40. Ripplet Intermediate Type Cylinder Head. I can use, and have made PL.91 shewing the modifications necessary to make this head suitable for 3¼" bore 6.5 to 1 COMP. RATIO. The floor becomes rather thin under .25 thick and may collapse. It is worth while to record that the development under went these changes. Ex.S.1383. Ex.S.1384. Ex.S.1758. Ex.S.1869. and finally .100 milled off the bottom face which made the capacity 111 c.c., we require 104¾ for this 3¼ bore engine. The parts which were created for this head are not rational for instance, a special length of inlet valve, and a different inlet valve seat. There is another feature I do not like is the almost impossibility of getting a spanner on the Spark plugs. However, if we accept the above, we can use the head with a milling operation to clear the Exhaust Valve and .040 milled off the bottom face. JNR.{Charles L. Jenner} | ||