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).
Daily report on performance tests of a Paulin Bentley II at Montlhéry, detailing speed and engine data from three separate tests.
| Identifier | ExFiles\Box 160\3\ scan0184 | |
| Date | 1st February 1939 | |
| To. Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe} 1379 Levallois. Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe}I/JAB.II.2.39. DAILY REPORT. Paulin Bentley II.- B-27-LE. Montlhéry. Funnel shaped intake fitted in place of centre lamp at front and metal flexible pipe taken to front end of air silencer. 1st Test. LM.8 Needles. 6.00 x 19" Track smooth tyres rear only. Best lap speed 177.784 KPH. Mixture control central (3 laps) 110.45 MPH. LM.8 needles set flush. 169.255 KPH. Mixture normal. 105.17 MPH. 8 laps completed. Max.3600 rpm. Oil temp. 120°c Water " 75°c 2nd Test. As before but with LM.7 needles fitted flush (stronger). Best lap speed 177.784 KPH. Mixture control central. (2 laps) 110.45 MPH. 177.150 KPH. Mixture normal. 106.25 MPH. 8 laps completed. Oil temp. 120°c 3rd Test. As 1st Test but with LB.5 needles fitted flush (stronger) Best lap speed 177.784 KPH. Mixture control central. (3 laps) 110.45 MPH. 174.404 KPH. Mixture normal 108.423 MPH. 8 laps completed. Oil Temp. 128°c Track conditions....... Dry. Barometer............. 762 Wind.................. Nil Air Temp.............. 13.5°c Humidity.............. 78 Above 90 m.p.h. with cold air at pressure needles should taper much more rapidly as shown by the above tests. The above figures give an idea of characteristic required. With control in central position jets are pulled down approx. 1/8". It was decided from these tests to retain LM.8 needles for the hour run and Sr. (driving) to operate the control to the central position when 90 m.p.h. was attained. This was thought the best for consumption. No doubt LM.2 or 3 needles would be correct at top speed full throttle with cold air into silencer under pressure at front of car, but may be far too strong at part or lower speed throttle openings. Car brought back to Rue Gide Depot for dismantling and inspection. Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe} [Signature] | ||