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).
Analysis of different cylinder block design and manufacturing methods, focusing on water spaces, studs, and wet liners.
| Identifier | ExFiles\Box 86\1\ scan0235 | |
| Date | 5th April 1937 guessed | |
| (sheet 2) wider water spaces on the sides, thus making a more substantial sand core, and in a few cases enabling the water space between the cylinders to be eliminated, a thing which could not be done on the R.R. cylinder. We have consulted the foundry who say that this widening of the water space at the sides would help them even if the space between the bores is not increased. It involves widening the engine and increasing the tappet centres. (2) We have investigated using short studs or bolts to hold the cylinder block to the crankcase, and find that the only difficulty is the stud at the forward end, where it is interfered with by the wheelcase projection. We believe we might overcome this in an acceptable way, but this does not help the scrap difficulty, or the bores projecting into the cylinders. Furthermore, the proposal shortens the water jacket 1.500 whereas we wish to lengthen them to assist in oil cooling. (3) The projection of the cylinders into the crankcase is a difficulty because of their thinness. This can be dealt with by spreading the centres, which would automatically give greater water space between the bores. The lengthening of the engine would be of the order of 1.000. We can stand this on the car, but it upsets the crankshaft proportions. (B). Another way is to use wet liners on the present cast iron block. This assists the casting difficulties, but distortion due to bolting is still a difficulty because we find we cannot cast long bosses in the block without risk of porosity. The engine length is not increased. (C) There is however a method of arranging the present cylinder block with wet liners, using studs, into short bosses in the block, independent studs being used to hold down the head, and other independent studs for the crankshaft bearings. The cylinder studs are nutted up permanently from inside the crankcase. In this scheme the engine is not lengthened, the castings difficulties are overcome, the projections into the crankcase lose their disadvantages, the distortion due to bolting down is eliminated, and the water jackets are not shortened. | ||