Maximum Aadvance Hi Octane Spark Map

[Gelf VXR]

The maximum spark advance in the hi octane map seems to peek at 40 degrees. Ive seen it said that advancing spark in lean cruise cells can iimprove econmy by tuning MBT, however some of these cells are at the 40 degree maximum. Can these cells be pushed past 40 degrees?

[N0DIH]

On the LT1 the max timing is 46 degrees. That seems around the practical limit for timing on a V8 engine.