The downpipe is the main thing you wanna check, if it still had the U bend by the 02 sensor then it's a stock DP and a major exhaust restriction point. If it is stock that should be the FIRST thing you replace if you keep that pulley on there! Also get a tool for scanning the car since even with an aftermarket DP you can still be getting KR. Lots of people on here use the Torque app with a Bluetooth OBDII reader.
Here's a link that all new owners should read whether that have a previously modified car or plan on doing anything to it in the future:
http://www.gpona.com/forums/97-03-gr...ar-t21802.html
