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).
Progress report on the testing and development of B.III and Wraith III engine units.
| Identifier | ExFiles\Box 155\2\ scan0218 | |
| Date | 21th May 1938 | |
| -2- B.III No.1 UNIT (a bed) -Cont'd. {John DeLooze - Company Secretary} By when above are complete pistons with a raised crown will be available for trial. Object of this is to have identical heads for B.III and Wraith yet with a compression ratio of 6.5 and 6.0 respectively. WRAITH III NO.4. (a) Continue investigation on induction systems and variation of distribution with carburetters. (b) This unit has special Chrome iron cylinder block and oil consumption to be checked in 1 hr. runs until consistent reading is obtained. These runs to be carried out on Ethyl fuel and Mob. Arctic. (c) Check valve bounce with silencer fitted as 3 Inlet valves have been produced by Belgrave Co. and are slightly heavier than std., being unmachined on the under side of head. (d) A periodic check of gear noise and backlash to be taken as this unit is equipped with latest set up, i.e. Attwater's fibre camwheel and no balancer. (e) This unit is also equipped with cast Monikrom camshaft and we wish to get as much high speed running done with thisas possible consistent with development work which is being carried out. B.III NO.3 UNIT. This unit has been assembled and requires testing prior to being fitted in the first B.50 chassis. There are no new parts that require running in, and testing should be carried out as follows. New parts fitted since last on test are - (a) Attwater's fibre camwheel. (b) Delco distributor with spring drive. (c) Std. Wraith valve springs. Cont'd. {John DeLooze - Company Secretary} | ||