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Ignition timing

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With fuel tuning in VE mode it makes a lot of sense as the numbers in the table actually mean something. And we can tell if changes we make to the engine have improved the VE. After watching videos on the site and also one where Andy wyatt shows the equation which the ecu processes the injector output in VE mode it has got me asking the question that knock aside and providing the base ignition timing is perfectly set and system delay accounted for what is it that stops the ideal ignition timing to be able to be worked out? The burn speed of the fuel would remain a constant. Would the cam timing effect the ideal point? Would the rod to stroke ratio effect the ideal timing to achive the maximum force on the crankshaft? How could load be took into the equation? Every engine has different charteristics but something causes these that could be accounted for.

Unfortunately it's not quite that simple. There are dozens of factors that will affect the optimal ignition timing and while yes, this could be modelled, the reality is that outside of professional engine development or OE manufacturers, this isn't viable for enthusiast or professional tuners. Keep in mind that even the burn speed of the combustion charge isn't actually fixed but instead will depend on the engine load for example.