want more power? change gearbox to manual. u can lup turbo,
change thousand and one things, but ur weakest link will still be
the transmission, which will not be strong enough to transfer the
power effectively to the wheels. its like a muscle man trying to
lift weights using a bar made of jelly.
alternatively, u can do mods like intake, exos etc and gain about
5-10% more power. complete waste of time and money IMO.