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).
Vehicle performance tests focusing on petrol starvation and acceleration issues under various conditions.
| Identifier | ExFiles\Box 149\4\ scan0391 | |
| Date | 17th August 1937 guessed | |
| ( 2 ) and delivered petrol normally. The air temperature was 37°c and the petrol in the tank 48°c. Running was resumed with no trouble until 33 miles further on, high speed starvation with the usual symptoms in limiting speed to 60 MPH. or 40 MPH. on either half of the pump. The air temperature was still at 37°c. Slower road conditions were then met with and the trouble no longer noticed. In the evening, the air temperature fell to 33°c and after a 10 minutes halt with U.B. 72° Water 100° and Oil 100°c, no hesitation occurred on acceleration and no more high speed starvation was experienced. 2nd Day. The car was tested on the Pic du Midi in the morning and no vapour trouble was experienced with air temps. between 32° and 26°c under strenuous conditions up to 8,500 feet, the highest temperatures ever likely to be reached at these altitudes in Europe. In the afternoon on the plains, further starvation tests were carried out. After a 15 minutes halt with air at 35°c, temporary starvation on acceleration for 30 seconds only was experienced. Two 10 minute halts with air at 34°c each showed only 10 seconds hesitation at full speed on second gear. No high speed starvation was experienced at these temperatures, but symptoms of it being on the border line were felt and confirmed by finding that the petrol supply was not sufficient to run above 60 MPH. in second gear, although this is neither advisable or necessary. 3rd Day. Run back to Châteauroux. A further series of tests for failure on acceleration after 10 minutes halts were made. Air 32° Water 97° Oil 93° U.B. 72° No failure. Air 31° Water 98° Oil 98° U.B. 72° Momentary hesitation at 55 MPH. in 2nd gear. Air 33° Water 100° Oil 102° UB.76° 20 secs.hesitation at 70 MPH.in direct gear. No high speed starvation experienced during run with air temperatures between 31° and 33° throughout afternoon. | ||