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).
Preliminary analysis of the cost and weight for new high-power engine units.
| Identifier | ExFiles\Box 148\2\ scan0020 | |
| Date | 26th October 1938 | |
| 1260 also 1129a (See 1129a for Print attached) SHEET. Cost Sg.{Arthur F. Sidgreaves - MD} from Rm.{William Robotham - Chief Engineer} Ms. c. Ry. c. RHO. c. Da.{Bernard Day - Chassis Design} c. RFS. p. De/jmr. Hml/R.26.10.38. HIGH POWER ENGINE UNITS. We have now got a preliminary picture of this engine with regard to cost, weight and power output. Cost. A note has been circulated REC/CANE/LS.17.10.38. indicating that this engine can be manufactured for £80/3/3. This compares with the present factory cost on the Wraith engine unit of £153/10/-. It is clear that such a big reduction could not possibly have come about by design only, and that a large proportion of it is due to the fact that new methods of manufacture will be employed. We hope that further reductions will be possible in the material cost of the engine by judicious buying, but the £33/6/- material cost of B.60 engine compares very favourably with the £41 comparable material cost of the Leyland Cub power unit (This figure should be treated as confidential). When electrical equipment is added to the cost of the engine and this figure is then taken as 11% of the total cost of the car (as deduced in Hml/R.24.11.37.), it is reasonable to suggest that the price of this unit makes it satisfactory for an £800 car. It is clear, however, that similar types of engines are to-day being made for about 30% less cost, so that we must not relax our efforts to economise still further wherever possible. Weight. The Foundry point out that when they get into production they expect to be able to save a further 8 lbs on the weight of the block and crankcase casting, which is the major portion of this engine, due to better patterns. If this can be achieved, the weight of the B.60 engine in production should be at least 30 lbs less than the existing 4 1/4-litre engine. | ||