Stryker,
Not a pro, but a consumer here.
1) An Xcal 2 SF will allow you to adjust shift firmness from the handheld tuner. If you get the xcal from Dennis (like I did) or Lidio, the shifts will be better timed and firmer due to their tune. You can adjust from there.
2) No, you don't have to replace the clutches. However, I am extremely pleased with my Art Carr L2 kit which included new clutches. I ran with just the tuner for a year and had fun with it. The new improved tranny is even more fun.
3) The function of a torque converter is the same in every automatic tranny. Simply, it takes energy from the motor, turns it into fluid energy, then the fluid energy is used to turn the tranny gears. Basically, it performs the same type of function as you feathering the clutch in a stick shift. You don't need a different torque converter. However, higher stall converters let the motor come closer to it's ideal RPM for more power before the fluid energy is given to the gears.
Hope this helps. There are folks who know way more and could give details, but I think you should get and Xcal2 SF from Dennis Reinhart and start there. You'll learn a lot by using it and Dennis's base tune is fun.
Good luck.
Rich
Magindat: (majin-dat) Imagine That.
2013 Ford Taurus SHO
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