Well, you asked for tips...
1) Remember, breaking as late as possible usually isn't the best choice. Sometimes if you break a little earlier - you can carry a lot more speed through the corner.
2) Use the whole track. Many people around here yelled at me because I was crossing the white lines when trying to make the track as wide as possible. I didn't notice I was crossing the lines, but anyways. That was in my tryings to make the track wider. It's always better to take the corners wider.
Also, are you using any assists except the racing line? If you use - you can remove TC. TC slows you down.