The shift kit will be a nice mod for you. You will gain some performance gain, but mainly, it makes it much more fun to drive. You should be able to squeel second at WOT depending on your tires and road conditions.
You can build up an AOD to out perform a T-5 on any day, but it will cost you more money than just purchasing a T-5. If you prefer the automatic, they can be built right. For instance, Lentech makes an awesome AOD that will hold 600+hp levels and run more consistantly than any T-5.
Basically, to make an AOD run with a T-5, you need 3.73 or 4.10 gears, a shift kit, a 2500-2800 rpm torque converter, and you should also add a tranny cooler. This can run upwards of $1300 if you buy the good stuff (which is a must with an AOD build...companies like Precision Industries, Transgo, etc...). Further than that, to handle constant racing and high horspower applications, there are internal modifications to clutches and bands, etc that need to be made, or you can buy a complete tranny from Lentech already done up.
--nathan
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--silver_pilate
'91 GT, Built 306, Wolverine 1087 cam, ported Windsor Jr. Irons, and all the goodies...click the link to the left to see a full list of my mods...
Tried and True 302 Being Built to Outrun You! heh heh heh...
--Texas Panhandle--
Check out my site