The ignition system should be fine up and well past 7psi. If you get some spark blowout gap the plugs down a bit...you should be running colder plugs anyway under boost.
The electric fan turns on when the ac is on for extra cooling, I believe it may turn on when the engine hits a certain temperature as well. Some people have removed the mechanical fan altogether and wired the electric fan to a relay so that it is on when the engine is on.
Any more questions:
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