It all started with a 90 degree turn to a jump I accidentally made... then I thought about how to make more frustrating turns and speed checks. The track has been made easier than what I originally planned. I couldn't verify a clean lap because I would always choke.
Backwards for GPS
Track Summary:
1. Hairpin into sharp off-camber left into jump. You need at least 175 speed to clear the jump smoothly. Stay on the inside edge of the hairpin and turn to the left a little before the actual left track so you don't crash into the wall at the jump. If you turn too early, the hump of the banking will mess up the jump.
2. Offcamber hairpin into transition to a banked/flat straight into gap-crossing. 180-185 is safe on the hairpin at the outer edge. I have placed a pylon to bridge the gap between two blocks diagonal of each other. You can drive over smoothly, but if you don't you'll get hit with the collision acceleration penalty which makes the next jump difficult.
3. Narrow hairpin into jump. You need at least 258 speed to smoothly clear the jump. There are many ways to get to that speed through the hairpin (drift, drive the outer edge, racing line, etc.). Just don't touch the grass or the outside barriers.
4. Hairpin up a hill. Again, you'll want good exit speed after this part. There is a pylon on the outside edge of both corner entry and exit making it awkward to drive a smooth racing line. Additionally, if you have too much speed, you can easily fly off into the wall.
5. Diagonal jump into jump into finish. 265+ is a good speed to have here. Aim approximately where the arrow sign is pointing down on. You will need to let off gas to adjust your landing spot. Ideally you want to land on the flat->banked straight for a smooth landing. You need 280 speed to clear the last jump without touching the small hill before. If you're too fast, you'll crash into the finish hoop.