The WS6 will beat him hands down. Not trying to be biased (because i own one), but i have never seen a stock S2000 run better than a 13.8 at the track...i have seen an s2000 spraying and ran 13.9 on moderate traction. On the other hand i have personally run 13.02 bone stock - i have seen stock WS6 M6s run high 12s - especially here in florida. The t/a has the torque and will most likely leave him fairly easily....those S2000's may have some Hp, but they have to get way into the power band to start making it to the wheels.