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).
Visit to Cadillac, discussing engine comparisons, design choices, and material experiments.
| Identifier | ExFiles\Box 173\4\ img060 | |
| Date | 4th December 1935 | |
| To-day we returned to Cadillacs and talked to Seaholm and some others. The Cadillac expert knows nothing about chucking except small clearances, and was greatly surprised when I demonstrated that the Chevrolet was very bad and the V-8 Cadillac not as good as a Buick. To-morrow I hope this research expert will know the answer, after which I'll try Hudson's. They are only interested in short engines to get a better ride. They have not made up their minds about rear engined cars, the difficulties being too much weight at the rear and a lot of waste space in front. They have done nothing further with variable pitch fans except take them off production owing to manufacturing difficulties, and are experimenting with variable speed fans, on none of the G.M. engines do they try for a tick-over speed under 400 r.p.m. Nothing has been done to the engine mounting to prevent excessive movement when idling erratically. They have experimented with Cadmium bearings but find that at high oil temperatures the fatty acids in the oil rapidly dissolve the bearings with consequent failure; sometimes in a very short mileage the metal completely disappears. In an engine that runs hot but does not use much oil, and hence gets a high acid content, the bearings corrode when the engine is stationary. Pontiac standardised this material and very hurriedly changed back to whitemetal. If the corrosion does not take place, the life is 17 times that of whitemetal. The Cadillac V-12 connecting rods will last 8,000 miles at 80 m.p.h. which life is considered adequate. They give no trouble in service. As regards V-8 engines, these originally had serveral rough periods on the drive due to crankshaft lateral deflections. 100% balance of centrifugal masses and piston couple helped considerably but the flywheel still vibrated at high compression ratios. Flexibility cured this (see picture) but when the lateral deflections were eliminated and the bearing loads reduced, torsional ones became apparent. | ||