My name is Jeff and I am new to gpforums. I have a 1999 GTP with a 3.5 pulley and 3" offroad downpipe. I am a lot more familiar with 4g63s as I have owned an maintained a DSM for 4 years. Anyway, I have read a decent amount about l67s and am not totally in the dark. My issue is my car pulls decently through 1st and most of te way through second but when I hit 80 or 85 it falls on its face. My first thought was KR but it has done the same thing even with the stock pulley and it seems to be a little bit better in colder weather but regardless it still happens. Has anyone had a similar issue or experience with this? Any help is greatly appreciated.