really wanting to do this

 

Awww geez, not this again...

Look, a 5-speed was chosen for a reason because of the 2AZ torque specs.

-- If you want fuel economy, trade your tC in for a Yaris.

-- If you want to make your N/A tC go faster, get a stand alone EMS, raise the rev limit and get rid of the 127 mph limiter... you could probably get 138, but you're never going to make that speed on a track unless you run Talladega or the Bonneville Salt Flats.

-- If you REALLY want to swap with a 6-speed auto, your friends will laugh at you, your girlfriend will leave you, and you'll most likely go insane after you realize you wasted all that money for nothing.