Assuming the WS6 is stock and he can drive it will run 13's. You are going to need N20 to beat this guy. THe 97 GT isnt the best year for power and a vert is heavier yet. ZEX has a nice kit. Get the ZEX kit, some pulleys, 3.73 gears and some sticky tires.
The gsx you might be able to hang close to if its stock and you launch like CRAZY. But if hes got the standard mods it should go mid low 14's with a crazy launch.
Skyler
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-1989 Saleen Mustang #406-
TFS TW Heads, E-303, Edelbrock intake, 70mm TB, 73mm MAF, 24lb injectors, 1 5/8 shorties, Off Road H, 3 Chamber flows, Jaz Race seats, Back seat removed, sub-frames, Roll Cage, and a 80 shot of N20.
12.54@107.4 Motor
332RWHP, 350rwtq