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).
Notes on aero carburettor testing methods, a visit to Briggs to review car designs, and tappet designs from Wilcox Rich.
| Identifier | ExFiles\Box 173\4\ img186 | |
| Date | 1st January 1936 | |
| -3- They would not give me the drawings RHC.{R. H. Coverley - Production Engineer} wanted of the aero carb. testing equipment, but I have a good idea of its functioning. The air supply to the carburetter is measured by the pressure in a 6" dia. venturi on a sloping (1 in 8) water manometer tube, the gradient being corrected daily for temperature and pressure. G.M. Research say air flows cannot be measured accurately this way - that the only way is to pass the air through a Rootes blower driven by a separate variable speed motor so that there is no pressure difference across the blower. By knowing the speed the flow is calculated mathematically. They use this method for testing wood models of inlet ports. Yesterday Da.{Bernard Day - Chassis Design}, Park and I visited Briggs and their chief designer, Tjaarda, showed us all the futuristic, orthodox cars, and a complete rear engine car seating 6 people (2 rows) on a 125" wheelbase, and capable of 110 m.p.h., with a Ford V-8 engine. A nice looking job with no frame, weighing 2800 lbs. and exceedingly stiff torsionally. Weight distribution 2:1 rear to front, which must not be exceeded for good handling, and which necessitates the engine being in front of the rear wheels plane. We have a book of literature on this car. At Wilcox Rich. Obviously they claim their tappet to be better than the G.M. type and Cadillacs agree. They added to the information obtained from Cadillac that to prevent the valves being held open when bouncing - I Tappet > I valve etc. Tappet Spring Valve Spring An additional tappet spring like we use must not be fitted. The plunger has .0003 to .0005 clearance and a sharp bottom edge to prevent sticking when dirty. | ||