Trial by Dirt

Trial by Dirt is an Off-Road Challenge in GTA Vice City.

Complete a dirt track course using a Sanchez.

This is an optional endeavor, but it is required for 100% completion of the game. It's not time-sensitive, meaning it can be played at any point, even after the main storyline is completed.

Trial by Dirt - Off-Road Challenge Details:

The Trial by Dirt side-mission is a two-lap checkpoint mission, where the player has to clear each checkpoint using a Sanchez without falling off of or destroying the vehicle.

The mission course is the reverse of that of Test Track, and can be accessed by entering the parked Sanchez on the dirt track in Downtown.

The reward for completing this mission is $100, and every subsequent completion accumulates an extra $100. However, setting new records adds challenges to the track, therefore:

After the first record is set, four explosive barrels are placed on the last stretch of the track.
After the first record is beaten, rain will begin to fall on the track, making it slippery.
After the second record is beaten, a group of three Haitians armed with Machetes, riding unique black Sanchez' will spawn and pursue the player.