I rember that with Stock Tires (Racing Hard) my best was a 5.51.xxx, with Racing Soft I can do easily around 5:30 - 5:35 considering that my best with the Minolta is a 5:23
I managed a 5:52.445 on racing softs with a g27... I find that pretty good for myself being my PB on the ring and because I HATED this car until a day ago... haha