if your talking about the speed signal from the dash to the ECU i did it on my 1G-GTE. it disables the speed cut, and throws and error after 3000 rpm. that was all it seemed to do, not sure about your car but the 1G-GTE's throw an error (light up the check engine light) if the car is above 3000rpm and for longer then 5 seconds and it thinks its going less then 2Kmph.