In previous versions of the game you needed 3 consoles. No idea if they bothered to put this feature into GT Sport, it is something that not many will ever use.
Triple screen support is not just a matter of being able to hook up three screens, you also need the CPU/GPU/memory capacity to output 3 times the normal amount of pixels at the same frame rate. That's why you needed 3 consoles and 3 copies of the came to do this on PS3. It's also for this reason there's no full VR mode, but a limited one: not enough resources on a single unit to do it.
This with the bumper cam and I'd sit real close so i feel like a fly smashed to the front bumper. In this instance though my fly eyeballs wouldn't be smashed, just my body. This would ensure that I would be solidly stuck to the bumper but still able to see in widescreen.