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).
Developments in 12-cylinder engines, automatic clutches, and vibration damping in US cars.
| Identifier | ExFiles\Box 43\4\ Scan335 | |
| Date | 30th January 1932 | |
| Y4024. x3993 To R.{Sir Henry Royce} From Hs.{Lord Ernest Hives - Chair} c. to SG.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to Hy.{Tom Haldenby - Plant Engineer} Hs.{Lord Ernest Hives - Chair}1/MJ.30.1.32. 12. CYL. ENGINES. It would appear that the twin six engine is rapidly replacing the straight eight on the big cars in U.S.A. Recently the Packard, Lincoln, Pierce Arrow, Auburn, have come out with twin six engines. We attach a list showing the capacity. Apparently our proposed size 3 x 4 1/4 is about right if we are to compete with these cars on performance. Another new feature which is rapidly becoming standard on a number of U.S. cars is a Vacuum control for the clutch. From the reports we have had, this appears to work exceedingly well and saves the driver a lot of fatigue especially with the present traffic lights. When driving in traffic, as soon as the accelerator pedal is let up the clutch is automatically withdrawn so at a traffic light it is not necessary to keep the foot on the clutch pedal and the gear can be left in ready for an immediate start. As soon as the engine is opened up, the clutch is automatically engaged and the car moves away. It also makes change gear easy. On most of the cars there is a control so that the device can be put out of action if desired. We think it may be a very good alternative to the fluid flywheel. We have asked Rh.{R. Hollingworth} to look into it, and if possible bring back a set of parts so that we can try it out on one of our cars. It will be noticed that on several of the latest U.S.A. models an odd angle has been adopted [handwritten: for the cyls] the claim for this is that it reduces torsional vibrations. The cars however are still fitted with crankshaft dampers. We are obtaining more information on this point. Hs.{Lord Ernest Hives - Chair} | ||