Cadillac ATS-V with an error?

Hi, I was driving a 2016 Cadillac ATS-V and noticed the braking wasn't very efficient, so I upgraded the brakes. Even then, it didn't handle corners well, so I upgraded the suspension, sway bars, and tires—but it still didn't corner properly. While testing it, I realized that when braking, the wheels wouldn't turn fully until the car came to a complete stop. Do you know if there's a way to fix this? Is it a glitch, or is that just how the car is? I've tuned other cars before and never ran into this issue.