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).
Report comparing standard and external air intakes, detailing temperature readings and performance conclusions.
| Identifier | ExFiles\Box 85\4\ scan0196 | |
| Date | 29th August 1938 | |
| -2- Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe}3/JH.29.8.38. Temperatures under fast running conditions. Standard Air Intake. External Air Intake. Air at carburetters 40°C. 19°C. under bonnet air 43°C. 43°C. external air. 18°C. 17°C. Conclusions. Performance was improved by the external air intake. The 20 to 60 M.P.H. acceleration figure showed an improvement of over 5% corresponding to an approximately 5% increase in BMEP prophesied by Test Bed. The very slightest hesitation was detectable when the throttle was snapped full open at low speeds. This however would be overcome by fitting damped pistons in the S.U. carburetters. No improvement in performance was recorded by strengthening up the mixture when running with the external air intake. Similarly no increase in maximum speed was obtained with this air intake with normal or strengthened mixture. Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe} | ||