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).
Proposed rationalised replacement for the Wraith model, designated 3.B.50.
| Identifier | ExFiles\Box 111\3\ scan0146 | |
| Date | 26th November 1940 | |
| Sg.{Arthur F. Sidgreaves - MD} from Rm.{William Robotham - Chief Engineer} Wraith Rm.{William Robotham - Chief Engineer}7/ML.26.11.40. WRAITH REPLACEMENT. We are asking you to try 3.B.50. This is a fully rationalised replacement for the Wraith. If you look at PL.139, it corresponds with the second column in Scheme 2, i.e., it is a 4-light Silver Wraith (only with the wrong radiator). It can either be sold as it is or with the front wheels brought back 4½", making the wheel base 10'5½" as shown on the print. The wheel base can only be shortened with the new engine. We shall recommend the shorter car for production unless anyone objects to the appearance. 3.B.50. is fitted with a new cast-iron engine, having the novel high power cylinder head. You have previously tried this engine as an 8-cylinder but not as a "6". Trying a "6" will give you an opportunity of comparing it directly with the unit it is going to replace. You will note that, due to the increased power output and reduced weight, 3.B.50. is almost 10 m.p.h. faster than your own car. This is not of great interest on an automobile of the Wraith type but will be an asset when this unit is standardised in the Bentley since, on this chassis, we are struggling with increased body dimensions and trying to maintain performance. We shall only gain a small fraction of 10 m.p.h. on the Bentley because to increase the car's speed from 90 to 91 m.p.h. requires more than twice as much h.p. as to produce the same speed increase at 75 m.p.h, On the attached list we give a few details concerning the two cars. The basic reason for producing 3.B.50 was to reduce production costs by :- 1. Simplifying and reducing the number of pieces in the chassis. 2. So arranging the design that 90% of the pieces in this car are common to a range of cars which may have engines from 5½ to 3 litres displacement andhave wheel bases from 11'1" to 9'2". - Continued - | ||