More gt4 video here (about 100 videos) :
http://www.ekila-forum.com/index.php
My gt4 video on YOUTUB (15 video,only GT Mode), my name is gt4mike in Youtub :
http://www.youtube.com/results?search=gt4mike&search_type=search_videos
ok so i just watched like the first half of your vid on youtube. i noticed aloooot of understeer especially @ initial turn-in. too much front camber maybe?