Hey I just put a BBK Twin 65 mm throttle body in my 98 cobra. It keeps idling at around 1300 to 2000. I tried adjusting the idler screw but to no avail. Sometimes it will come down if i restart the car. Could it be something with the TPS?
You need to get a volt meter and connect it to the TPS, then adjust its position on the trottle body ever so slightly. The TPS can accually pivit some on the trottle body when not torqued down, this pivit will allow you to put it in the correct position. Mine stock was about .92, try to get it between .90 and 1.0 and it should run fine. Good Luck.