im thinking of buying some nitto or mt street drag radials for going to the track but what kind of difference would i see in 1/4 mile times

 

It depends on your setup and how hard you launch. If you don't launch hard then Nittos may be all you need. If you have steep gears and a good torque converter (for an auto) and are spinning the Nittos then you may need the ET Streets to get your 60 ft times down to where you want them.
Whay kind of setup do you have?

 

i have a 97cobra pretty much stock but if i try to launch at like 2000 rpm i just roast my gforce sports. im thinking of also getting some 3.90s soon

 

Mickey Thompson ET streets are a good cure to your problemo.

 

Nitto's are the worst hooking dr, but last the longest. BFG's are a good middle ground tire, I pull 1.5x 60 foots on my 275/40/17's. The M/T's hook the best, but wear really fast. So it all comes down to what YOU are doing with the car.

 

Get a seperate pair of wheels and swap the tires on race day. If you just have the usual mild bolt-ons than get the ET Street radials to cure any tire spinning you might have. Heavy mods and a manual transmission will neccessitate getting the bias ply ET Streets, according to Mickey Thompson.
BFGs are good too, my dad uses those on his Grand National (3.42 gears, lotsa low-end torque) and says he couldn't break them loose if he wanted to.