I look forward to seeing what tires he's running as well...It will be interesting to see if Rivian's Senior Performance Test Engineer, Gardner Nichols, who will be running their R1T entry at Pikes Peak this summer, will have the factory speed limiter enabled for the run up the mountain. I would guess the truck will be running custom software to enable it to hit a higher top speed, along with lots of other modifications for safety, performance, etc. At the very least it will have some grippy tires, roll cage, containment seat etc. But I can't imagine a competitive run will be had with the factory speed limiter.
Relevant thread: https://www.rivianforums.com/forum/...formance-test-engineer-gardner-nichols.12244/