Question 1.
Remaps on turbo charged car mainly results in increased boost pressure and fuelling.
Only the "lesser" tuners just alter the boost and fueling. The more reputable tuners can alter a whole host of other variables, with at least 30 different parameters to play with on the MED9.
i can prolly guess which tuner you are implying...but the OP didn't want too techy an answer so i was just pointing out the main gist of a remap really...which is boost + ignition + fuelling.
but i think he wants to know a bit more about boost control / wastegates / actuators / n75 valves etc probably.
