very basic tuning, of course you need to also factor in EGT, knock, IAT, etc.
download something like Virtual Dyno...
start with timing figures as low as 10 and flat across the board, but make sure your AFR is nice and rich to keep things from going bang
Do a 3rd gear run, inspect power/torque made
Increase timing by x degrees
Do a 3rd gear run, inspect power/torque made
Increase timing by x degrees
when you add 1x extra degree and you're making crap all gains - it's time to back off the timing a little..
of course you need to repeat this process multiple times to get it right...
another thing to note, you can ramp up timing as torque decreases... this is where you need to properly overlay readouts to determine this.. then repeat the same process but only after peak torque to redline.
If you live in Australia (which you don't) I wouldn't recommend this on the streets at all.. but I'm assuming you're from the states.. so go nuts.