So a few problems:
1) The portal that puts the player high in the air facing a wall needs something to indicate where the player is supposed to go, it is not at all clear.
2) The lack of coolant rings really breaks up the track's pacing, as the player is forced to slow down at certain points that don't feel appropriate(assuming the player tries to boost as much as possible).
3) The portal the player jumps off a wall to land in needs some indication of how the player is supposed to land, or needs to be rotated so that the player doesn't die when they go straight at it instead of rotating so they land on their wheels. I died when I got through it, and had no idea why until I died again and realized I was basically nosediving into the ground at the angle I was using.

Other than that it's a pretty decent track; good luck in future builds!