Thanks for posting those links. I'll comment as I get a chance to review them.
http://ntrs.nasa.gov/archive/nasa/ca...9930081891.pdf
I have taken a cursory look at the issues on the ink above and found several interesting issues.
1) The "assumption" by the researchers that the observed increase in EGT with respect to RPM is flawed. The measured change in combustion temperature with increasing RPM is actually lower due to the delayed thetaPP during the higher RPMs, therefore so is actual EGT. The effects are actually very small but the reading changes are significant. Why, then are they (and we in instrumented aircraft) seeing higher EGT READINGS with increases in RPM? The reason this is the case is that the probe has less refractory time to cool between pulses of hot air.--it will read the same (or even a lower) temperature as higher. This has only recently become appreciated (the last 20 years or so).
2) If one looks at the change in exhaust valve temperature as CHT is altered while holding everything else consent, one quickly sees the most direct correlation of CHT-EVT as compared the other factors.
3) The unusually high EGTs in this study are due to the low compression (6.5:1) of the engine. As expected.
4) Research and analysis of hundreds of events of pre-ignition have debunked the "assumption" during this test that pre-ignition is caused by high exhaust valve temperature. This is simply not supported by reams of data from pre-ignition events where engine monitors have been present to record the events.
5) Some of the "assumptions" from the 1930s and 40s are taking a long time to dispel (recently a CMI representative giving a talk to 300 LAMEs in the US assigned effects of pre-ignition to having been, incorrectly, detonation--and that's not an uncommon error).
There is, however, some very good data in this study which has been confirmed in the decades following.
Thank you for posting this 1947 study.