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).
Experiments comparing exhaust heated systems with water heated systems to reduce detonation and improve engine economy.
| Identifier | WestWitteringFiles\Q\February1927-March1927\ 37 | |
| Date | 2nd February 1927 guessed | |
| contd :- -5- exhaust heated system the water temperature may be lowered and so reduce detonation without impairing the distribution. Other tests have shewn us that the higher temp. of the exhaust hot spot compared with water heating has no disadvantage. In fact test bed results shew that improved economy may be obtained because a weaker mixture can be used and still maintain maximum power. The conclusions we have arrived at from these various experiments is that up to the present the best all round results have been obtained with the standard exhaust heated system which possesses the advantage of quickly reaching the temp. conditions of normal operation and is unaffected by the engine water temperature which factor has more influence on detonation than the hot spot. The unreliable action of the baffle valve in the exhaust down pipe is the only disadvantage we have experienced with an otherwise good system and we think that if this one trouble could be overcome we should possess a system equal if not superior to the best on other cars. The advantage of our system should be better appreciated in cold climates and give more reliable results than a water heated system. We are continuing some experiments on the lighter Phantom pipe in regard to the drainage of petrol from the distribution pipe back to the bend as we think a slight improvement may be possible in this direction. Hs{Lord Ernest Hives - Chair}/A.{Mr Adams} C. Lovesey. | ||