A good quality racing gasoline has a RON in the range of 110 to 115. The difference in the spread of RON is not very important to racing engines. The test and hardware were originally developed in 1931. The hardware was revised in 1946 with procedural changes made until the late 1960's. The MON engine runs at 900 rpm with a 300 degree mixture temperature.
Spark advance varies with compression ratio.
In a real world engine, MON is necessary to satisfy octane demands at wide open throttle. This is a very important number for racing engines since they spend a high percentage of their lives under high speed and high load conditions. Racing engines cannot afford to be short on octane quality, since detonation or preignition will quickly reduce a racing engine to junk. Good quality racing gasolines have MON in the range of 100 to 115. To cover yourself for extreme conditions, it is wise to have an octane cushion but there is no advantage to using a very high octane quality product if you do not need it.