Go to this web site and read up even if you dont use them . http://www.converter.cc/
I personally would suggest that you pick Yank or Vigiliante, someone who custom does your converter to fit your mods.
I am running a hotcam, ported heads, headers etc, and a 4.09 gear. I have the 3000 stall. So far I have been happy with the TC. A 2400 stall may be fine for a stock motor, but you can use more stall then a stock motor with your mods.
I sent it back to them to have it taken apart and cleaned etc. since I just had my transmission rebuilt again.
Dave at Yank suggested that I go with a 3600 stall instead of the 3000 for optimal performance. I did not do that and I wonder if I should have or not.
One thing you may want to consider when changing your TC is go with a plate style cooler instead of the tube style. They are supposed to be more efficient.
Oh, and on the subject of dia. It is my understanding that a 12in 2400 stall converter will feel more loose then a 9.5 - 10in 2400 stall converter at light throttle. The reason being is the turbines on a 12in are set at a less pitch so the stall can be increased. With a smaller dia. converter the pitch can be kept at a steeper angle so light throttle will be more responsive.
However the tradeoff is additional heat from a small dia. converter. But this can be taken care of with a good cooler.

 

from the yank website

Is a transmission cooler needed with my Yank high stall converter?

Not typically with the street strip converters below 3000 stall. The superior efficient design of the Yank converters generate less heat than our competitor's offerings, making trans coolers unnecessary in street/strip applications. For more hard-core racing applications (or converters over 3000 stall speed), a trans cooler is always cheap insurance to protect the transmission when "hot-lapping" the car.

Is a shift kit required or recommended?

Yank Performance Converters can achieve maximum performance and efficiency without the use of shift kits. Shift kits dramatically raise transmission line pressure to increase shift firmness. Increased shift firmness will not increase performance, but create unnecessary stress on the transmission and other drive-line components.

The cooler is something i plan on getting as a preventative measure but is the shift kit really more harmful than good?

 

Did you get the "YANK STEALTH 3000 " for $525?

 

FYI I just asked my co-worker about his. Turns out he has a 3500 and it is sloppy as hell. I thought it was smaller than that, I'd say a 2600-2800 would probably be alright, but naturally it won't produce as good a track times.

 

My experience with a TCI convertor - which is also built to your specific/car.
started with 3400stall - felt loose
sent back to TCI upped stall to 4000 and requested tighter feel - with 3.54 gears felt like car was stock.

Tranny pump disentegrated this past year and I changed the intake to a single plane setup so I sent back convertor to be checked and upped the stall to 4400 (only cost $140). Car runs fine on street and there is no noticable lag. Main difference is - I can footbrake to 2100rpm vs only 1700 with the 4000.

Go for one that is built for your car - NOT off the shelf.