Put the honeycombs back in. If the silencer hasn't been already removed, you can get rid of that. You can also cut the aircan to make the filter open to the air. But, the honycombs are there to straighten the air over the sensor and there's NO way you are flowing enough air to even make a difference.
A/T comes with 13G and 390's. The ECU is also programmed with different fuel trims and timing maps. The smaller turbo is to make it spool faster to feel like there's more power, the smaller injectors are because the turbo doesn't push as much air so not as much fuel is needed, the fuel trims are different to match the faster curve because it spools so quick.
You CAN brake torque with the stock torque converter although you'll only build a few psi. With my 1G, I could build about 5psi and it launched pretty good. I had the 14b with 450's and the MT ECU.