4R70W shift kit advice needed

I just bought a used 97 Tbird with the 4.6L and a 4R70W trans. The
trans shifts "normal" but I like firm shifts for longer trans life.
I'm not talking tire screeching neck snapping shifts (like what I did
to my old AOD :-) just nice firm shifts instead of the slide into
gear shifts, it has now.
I saw many shift kits for this trans by different companies. I'd
like to know what you guys used and what you recommend.
I'd also like to know if you tried any of the electonic devices like
from Hypertech or Superchip that not only reprogram the trans but
reprogram the engine for more power or mileage.
Please, let me know your thoughts and recommendations.
Thanks.
Dan S.

I would recommend doing the J-Mod on your tranny. What's a j-mod? It is a modification developed by the designer of the trans. It is a 2.5 on a 5 point difficulty scale for a diy'r. Check out TCCoA on the web. That is the Thunderbird, Courger CLub of America. If you own a Bird it is a must stop and see for car info on there forums. They are a great help and have good tech articles to assist.
Good luck.

I would recommend doing the J-Mod on your tranny. What's a j-mod? It is a modification developed by the designer of the trans. It is a 2.5 on a 5 point difficulty scale for a diy'r. Check out TCCoA on the web. That is the Thunderbird, Courger CLub of America. If you own a Bird it is a must stop and see for car info on there forums. They are a great help and have good tech articles to assist.
Good luck.
Yep, J-mod is the only way to go ...........

I heard that the J-mod does a number on the trans, but gives you AWESOME shifts.

I heard that the J-mod does a number on the trans, but gives you AWESOME shifts.
It really doesnt hurt the tranny if the tranny is in good shape. The problems come when you j-mod a tranny that has tons of miles on it or one that has had a rough life. J-mod-ing just opens some passageways to allow more fluid to pass and changes some of the valving to make things happen more quickly.

If the tranny has worn or broken clutch plates or overheated springs inside, it can cause these parts to fail. Thats why the suggest that you go through the tranny completely if you are going to J-mod it!!!!