I'm not sure if everyone's setups suffer from this but the biggest problem I had was understeer particularly when accelerating out of turns, once I got a handle on that (tried tuning it out but made matters worse lol) it wasn't so bad. Mostly a case of "brake > turn > throttle" so I'd line the car up and brake then turn in and get it lined up for the exit before giving it too much throttle.
Looking at the map I think the biggest corners I found for making up (or losing) time were 3, 4, 6, 8, 9 and 10. If I remember the speeds right this is about what I was going through them at:
Turn 3: turning in @ 55-60mph, accel. out at 65mph+
Turn 4: turning in @ 70-75mph, 2 wheels on the curb and accel. out @ near 80mph
Turn 6: turning in @ 75mph, accel. out @ near 80mph
Turn 8: forgot speed but start out wide for the turn in and hit the accel. about halfway down the hill
Turn 9: turning in @ 75mph, carry speed through and accel. out late around 80mph
Turn 10: turning in @ 75mph, accel. out @ 80
like I say though it might've been the way I had my car set up that meant I had to break in a fairly straight line and turn in / through without too much throttle to get the right line out before really giving it the beans but hopefully that helps someone somehow
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