Auto's are better for drag racing! If you want to get abit more out of the std auto it would be advisable to get the std convertor loosened up abit. Geoff @ the convertor shop can do this for about $250-$300. 2 mates of mine got there TT300zx's done & it pushes the stall speed to about 3000rpm, which will help get you off the line better, but it may spin more unless you have decent tyres.The mods i would do are : HKS pod filter, full 3" exhaust including dump pipe, 13psi boost, advanced timing,decent fuel & octane booster should get you a low 13 with some practice. If it was me for the dump pipe i would be getting a HPC coated twin dump setup from Custom Exhaust specialists. You can check them out @ www.cesracing.com.au
The SubZero modded TRY09's ran 13.4 @ willowbank with similar mods but std convertor. It would be advisable to make sure the ducting to the std intercooler is good as well, maybe make some better ducting up so that the air has to go thru it & not around it, also make sure the air can get out @ the back of the cooler as well!