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A very basic definition of MAP is: a set of instructions used by a fuel injection Electronic Control Unit. The ECU reads a number of inputs (sensors) and uses that info to give a specific output (spark timing and fuel output). This is done many many times a second in an attempt to keep engine systems adjusted for various conditions.
If a system was designed with just two inputs you could make a graphical representation of the MAP that might look like a spread sheet. For any two input values there would be one set of data to use as an output.
If you design a system with three inputs the graphical representation would look like a very complex 3D graph, lots of peaks and valleys.
A Ficht ECU uses six inputs (throttle position, crankshaft position sensor, water temperature, air temperature, alternator voltage and barometric pressure) as well as a calculated torque output to determine spark timing, spark duration, injector timing, injector duration, injector current, and oiling output. Needless to say a MAP for such a system is quite an undertaking to create.
I don't have a lot of knowledge on how a MAP is created but I'm sure that a lot of it is worked out on a computer. I do know that a bit of it is done through hard work and trial and error. An engine is run, monitored, conditions are varied, results are recorded and studied and the final MAP is hammered out. When it all looks good it is released for the public to use. That is when the education starts.
People use engines many different ways, each person with their own touch and each with their own boat setup. Not every possiblilty gets duplicated in a research setting (and I doubt if that could ever happen). With the Ficht MAP the biggest problem developed with flats boats. The load on the engine didn't match what the MAP expected and that resulted in a poor midrange performance.
The Ficht ECU records data and with the right program the information can be downloaded into a computer. The data is analyze and a new map program is developed. The change might be as simple as firing an injector slightly later during a certain rpm range. This new program can be uploaded into the ECU with a lap top.
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