timing adjustment obsessed Options

[eldrewado]

hey everyone. ive got a 99 5sfe celica. as many of you know this means i have a non adjustable distributer. ive been told the computer adjusts the timing.
so my questions are: how does the computer adjust the timing? what sensors does it use to read the timing? does anyone know how the sensor or ecu does what it does in the area of timing? my goal is to "trick" the computer into advancing my timing a bit for better highway mileage and maybe some more power. surely there has to be a way to do it. ive heard i could do it with the timing belt, but then i heard i couldnt. any input greatly appreciated. thanks

[eldrewado]

ok so after some thinking and research i realized it cant be done with the belt. that's for valves not spark. ive been told that i cant put on the older distributor (is this wrong?) usually putting the pot on the ait increases advance but also increases fuel. i can also try putting a pot on the MAP and the coolant temp sensor. ill probably do all three so i can play with it as much as i can. there is a device for o2 sensors called the EFIE which helps you control fuel and is recommended alot. i think with all of this working in conjunction after alot of trial and error (and maybe some 93 octane) i may start getting somewhere. any thoughts? has anyone done any of this on there celica?