No, I couldn't tell you how, I know how it was usually done, but I “had it ... done” by a mechanic that I know and that I call the Iroquois because of his cut. tifs and professional abilities
It's a UFO.
But I do not believe that he intervened beyond the mechanical intervention. It is the same as without any modification, when you put E85 in a car equipped with an ECU (on-board computer) thanks to the information that it obtains from the probes the computer changes all the enrichment and enrichment parameters. ignition point to reach the optimum.
When you make an advance of 4 ° hourly, you will simply greatly facilitate the task for the computer which will find itself in more suitable working ranges and will no longer be constantly borderline in its settings => to the point of not having a optimal adjustment, but the best compromise. But I am absolutely sure that there are some here who know the problem much better, I am only giving modest clues.
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