Boring Co shows 127 mph tunnel run without guide wheels

The system uses Autopilot alone, eliminating the need for extra wheels to keep the car aligned in the tunnel.

Elon Musk's Boring Co has released a video showing two Tesla Model 3 sedans racing across Los Angeles, one underground and one on city streets.

The Model 3 traveling through the company's test tunnel hits a maximum speed of 127 mph and completes the journey in 01:36 minutes, while the car traversing traffic takes nearly five minutes to reach the same point.

Boring Co appears to have dropped its plan to use a set of horizontal guide wheels to keep the car centered in the tunnel. Instead, the driving surface has been painted with lane markers that enable Autopilot to navigate the narrow passage.

"This is simple and just works," Musk said on Twitter when asked why Boring Co abandoned the idea of sleds.