you can get away with a stock clutch for a while as long as your not racing every single person that drives past you. I'd recommend the ACT stage 1 clutch and it can hold up to 243 ft-lbs. That's more than enough on drag 3 gen kit. I know that the drag kit on a 94-00 LS at 8psi produces 255 WHP and 216 ft-lbs at the wheels. And quarter mile time is 13.28 on stock clutch.....I have a link on overboost.com that they did this...here it is.
http://www.overboost.com/story.asp?id=57
That kit is the shiznit!!!! Hope that helps.