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).
Suggestions for the bonnet and radiator shutter temperature range.
| Identifier | ExFiles\Box 19\3\ Scan341 | |
| Date | 12th May 1930 | |
| x7572. To: H.{Arthur M. Hanbury - Head Complaints} from Cy. c. Sg.{Arthur F. Sidgreaves - MD} c. Rep. c. Hy.{Tom Haldenby - Plant Engineer} c. Db.{Donald Bastow - Suspensions} c. Hs.{Lord Ernest Hives - Chair} C. HHA. c. [REDACTED] C. [REDACTED] Oy1/DH.{D. Henderson - Showroom}12.5.30. Bonnet and Radiator. Referring to R2/B30.4.30 and R1/M.5.30 I would like to offer the following suggestions. Shutter Temperature Range. Mr. Royce suggests a maximum working temperature range of 30°C (54°F) namely from 70°C fully open to 40°C full closed. Mr. Royce also suggests this range can be quite considerably reduced. If powerful springs or spring loaded ball joints are avoided I believe this range can be reduced to 10°C at most. You will recall that on 404 MR we found :- Full open 170°F (77°C) Full closed 158°F (70°C) A range of only 7°C (Probably some of the internal friction is "shaken out" on the road) This car runs at 160°F (71°C) which, as Mr. Royce says, is probably too hot for best conditions. It is certainly too hot for the best "feel" of the engine which is much smoother around 140°F (60°C). Why we put the working temperature so high in spite of engine roughness was because :- (a) We found acceleration not so good at lower temperatures. (b) We desired a warm engine as a safeguard against oil-dilution in winter. Possibly neither of these arguments applies to P.II, cont'd.{John DeLooze - Company Secretary} | ||