A Microtech (or similar) standalone ECU would be what you are thinking about...
But the Stock ECU in Accents is actually pretty versatile as all the NA mods are really quite mild...
Just adding a set of extractors, 2.25" mandrel bent exhaust and high flow cat wont really warrant a standalone ECU...
However if you ad bigger injectors, higher capacity fuel pump, port and polish, Cams, underdrive pulleys and bore out the head you might need a standalone ECU...
If you have the money (and if i remember your previous post correctly) get a beta swap done straight up and go from there...
The Beta engine is much more responsive to modding (RPW in Perth will do it for $5000, drive in drive out no problems and a warranty to boot)...
It also starts with bigger numbers (104HP and 135NM, i think)...
Join:
Hyper Auto Club :: Index (there are a few members on there from Bris-Vegas as well)
And do some research...
Cheers
scythe