got a real simple cure for this..look in the ecu should be wire 27? im not sure exactly..its green with NO other color stripes on it...it goes to the tach and speedo. all you have to do is cut it (which will make your tach dead) or hook a switch on it...so after 100mph voila! hit the switch and the tach/speedo goes dead and you can go past 113mph which should be the cutoff for s13s . works on my car with nice results.