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).
Experimental features fitted to a car, including the crankshaft, cylinder head, carburetors, air silencer, and fuel system.
| Identifier | ExFiles\Box 179b\1\ img332 | |
| Date | 1st May 1932 | |
| To R.{Sir Henry Royce} from Hw/Rm.{William Robotham - Chief Engineer} c. to Sg.{Arthur F. Sidgreaves - MD} Tor. c. to V.{VIENNA} By.{R.W. Bailey - Chief Engineer} Hw/Rm.{William Robotham - Chief Engineer}1/XT.1.5.32. X5972 16.XI.IV. fitted - This car has a number of experimental features ENGINE. (a) Crankshaft. This has larger journals (2.250 dia) which enable the engine to be run up to ... m.p.h. with standard balance weights (Chrysler scheme journal & 1/3 the big end) without the critical speed being felt. (b) Cylinder Head. This is a J.1. head slightly modified to fit on a standard China cylinder block. It has a 6.2/1 c/r.{Sir Henry Royce} and 14 m.m. sparking plugs. This size of plug is fitted to enable us to get some indication of the performance of the small plug under high duty conditions. Both Lodge and ..... are making such plugs and they appear promising. (c) Carbs to EC.2924. We have fitted these with .9" dia. chokes to get good snap opening up. We are also doing work on the accelerator pump and diffusers with the object of getting the carburetters to function satisfactorily with larger chokes. We think that it may be possible to use larger chokes ultimately. We will report fully on these carburetters when we are satisfied and we know more about them. The consumption is about 15 m.p.g. at present. (d) Air Silencer. We have tried a resonance type intake silencer with some success. We are, however, reading it with the original silencer which drops about 4 B.H.P., as will be seen from the curve m.65. (e) Petrol Feed. J.{Mr Johnson W.M.} petrol lift fitted as we have no petrol pump design for J.1. This instrument is noisy when pumping, particularly dry, but this defect has been reduced by the manufacturers. Its operation produces flickering of the ammeter needle. GEARBOX. This is the latest production synchro-mesh box. EXHAUST SYSTEM. This is the existing standard 25 H.P. exhaust. | ||