i have 02 TAhoe LT stock... .whats the fastest it would run in the 1/4 or 1/8 if i built it all motor w/o FI ? and if can lists needed parts >

thanks alot!
Thats something you need to plan out yourself bro. Theres no way we could give you any kind of accurate estimate. A friggin school bus can run 12s with the right stuff, so that being said, there are literally thousands of answers to your question. We could never narrow down one particular parts list.
If you're serious about it, like really serious about it, go find a reputable engine builder and see what he can do. If you really want to make some head turning power, at the very least you're looking at boring out the motor and upgrading the internals, maybe getting the block blueprinted, complete intake and exhaust work (headers all the way back), and a custom tune. Depending on what kind of power you're looking at producing, you'd probably want to swap in a built 4L80E transmission, or you'll grenade the stock 4L60E after one pass on the track.
If you're just looking at simple bolt ons, then the same stuff applies without messing with the block too much. Intake, full exhaust, and tune. The parts themselves will free up alot of power, but the tune is what ties everything together and really wakes the truck up. Either route you go, good luck.