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).
Test results for a 40/50 engine on a test bench, examining performance with an exhaust heated throttle at 500 and 2000 RPM.
| Identifier | ExFiles\Box 50\3\ Scan185 | |
| Date | 1st September 1921 guessed | |
| Test taken on 40/50 engine on Test Bench. Engine fitted with exhaust heated throttle and collectors in each induction pipe branch with pipes to drain all liquid petrol into a glass flask. Standard 2" induction pipe. Fuel 20% paraffin mixture. Engine run at 500 R.P.M. full throttle. | Position of butterfly valve in exht: pipe. | Temp. of throttle. | HP. | Weakest mix: to maintain full power. | |--------------------------------------------|--------------------|-------|-------------------------------------| | Shut | 218°C | 22.5 | 18.5 pts. per hr. | | 10° open | 214°C | 22.5 | 18 pts. per hr. | | 20° open | 186°C | 23 | 18.5 pts. per hr. | | 30° open | 154°C | 23.5 | 18.5 pts. per hr. | | 40° open | 120°C | 23.7 | 18.5 pts. per hr. | | 50° open | 92°C | 24.0 | 19.0 pts. per hr. | | 60° open | 72°C | 24.0 | 19.5 pts. per hr. | | 70° open | 54°C | 24.2 | 20.0 pts. per hr. | | 80° open | 42°C | 24.2 | 23.0 pts. per hr. | | 90° open | 32°C | 24.2 | 24.0 pts. per hr. | Condition as above except engine run at 2000 R.P.M. full power. | Position of butterfly valve in exht: pipe. | Temp. of throttle. | HP. | Weakest mix: to maintain full power. | |--------------------------------------------|--------------------|-------|-------------------------------------| | 60° open | 202°C | 75 | ------ | | 70° open | 188°C | 77 | ------ | | 80° open | 158°C | 77.5 | ------ | | 90° open | 120°C | 78.5 | ------ | | ||