looking to run a 346-408 CI motor with an ATI procharger. Which auto will be the most streetable, and add fun at the track. .I am thinking a level 3 4l60E since it will retain overdrive... I do like the idea of a transbrake though.. Any input?

 

Its all about how much you intend to drive the car. My car is a weekend toy, so I opted for the TH400 with a large stall and transbrake. That pretty much gaurenteed that the car will never be road tripped again. There are a few level 3 4L60E's here in town. As soon as they got hit with big power they all broke. Unless I am mistaken there are no transbrake 4L60's.

Give up the A4. If you dont plan on driving it to work everyday, its an awesome tranny. The key to it being good for in town driving is the biggest tranny cooler you can find, with a powerful fan. It can live with a bigger stall if you follow the "the cooler the better" plan.

 

So you are recommending the TH400? I drive approx 50 miles a day.. No roads above 55mph (70ish). What can I get that will hold some power and still remain somewhat streetable?

 

For that much driving. Go level 4L60 Level III. I am afraid you will cook the tranny with that much driving at slower speeds.
You should call TCI or even Madman (built my tranny) and talk to some real experts. They dont want to sell you anything that will just burn up, and leave you pissed off. I would expect a very honest reccomendation from them.