I spent hours yesterday trying to beat my 15.67, but on my 3rd try this morning I got this time.

The bump on the first hairpin is about as fast as I think it's possible to get, as you can see I was a full car-length ahead of the ghost, which works out to about 0.3 seconds. However, the section after the excavator wasn't optimal, so there is still time to save.

If you can string together the first half of this run, with the second half of the 15.67, I think a time of 15.3x or even 15.2x is possible