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 report on different 'turbulent' type cylinder heads for the lighter Phantom engine to address detonation issues.
| Identifier | ExFiles\Box 42\4\ Scan050 | |
| Date | 10th December 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/ACL. c. to BJ. WHT. c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to RG.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} X3867 Hs{Lord Ernest Hives - Chair}/ACL1/LG10.12.26. LIGHTER PHANTOM ENGINE. X.699 X.3867 x1060 Some further tests have been carried out on the lighter Phantom engine with the 'turbulent' type head, the object being to test what influence the various heads had upon reducing the tendency to detonate and continued firing after switching off the ignition, both troubles which are manifest on the standard Phantom. Three heads have now been tested - the original aluminium head LeC.2229, the original head with the valves reduced to 1.600 dia., and the alternative form of head LeC. 2230 which has the smaller opening into the combustion space or larger deflecting surface between the piston top and the head. This sketch shews the types tried. In our previous report on this engine we stated that the clearance between the head and the piston was reduced from .128 to .058 for the purpose of a test. It was thought that the smaller clearance would promote Contd. [Text in blue box] Nº 1. LeC. 2229. 2.650 Nº 2. SAME AS Nº 1. BUT FITTED WITH SMALLER VALVES (1.600 DIA.) 2.250 Nº 3. LeC. 2230. 1.950 | ||