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).
Summary comparing the performance and reliability of various radiator matrices across different car models.
| Identifier | ExFiles\Box 150\3\ scan0097 | |
| Date | 21th December 1936 | |
| To Hs. {Lord Ernest Hives - Chair} from Rm {William Robotham - Chief Engineer} /Std. Rm {William Robotham - Chief Engineer} /Std.11/AP.21.12.36. SUMMARY OF COMPARISONS BETWEEN RR. HEX. TUBE MATRICES AND (a) PRESENT STANDARD MATRICES. (b) BEST MATRICES WHICH WE KNOW AT THE MOMENT. Attached is a sheet shewing in tabulated form, the above mentioned comparisons. The 25.HP. car figures given in the first column are derived by comparison of various test figures which we have taken. The corresponding critical air temperatures in column (3) refer to the 20/25.HP. engine, which was standard at the time when the last hex. tube matrices were standard i.e. they do not take into account the increase in HP. etc. of the 25/30 engine. They are directly comparable and show more clearly the meaning of the figures in column (1). The 40/50 HP. figures in column (3) are obtained from actual test figures and those in column (1) are derived from column (3) by taking into account the alterations in heat to jacket water etc. As regards reliability etc., it is difficult to give reliable comparisons, as complaints of leaks on radiators have not been recorded separately as matrix leaks or top tank leaks - with the 25/30. or Phantom II. type of radiator the latter type of leak is not infrequent. However, the following figures were obtained from the Repair Department (see attached sheet). It is significant to note that on the Bentley car, which has a top tank construction which does not cause top tank leaks, and which has always had Marston type matrices, no complaints of leaks or overheating have been received throughout the period during which it has been on production. We may mention that the Marston Mk.V. type of matrix which is now standard on both Bentley and 25/30. and the Mk.VI. type on Phantom III. is definitely stronger and more immune from leaks than the Mk.III. type which feature in the comparisons on the attached sheet. Rm {William Robotham - Chief Engineer} /Std. | ||