The Charlotte road course test was interrupted for nearly 2 hours because drivers were able to drive through the backstretch chicane. NASCAR has added speed bumps and a tire wall in addition to the existing rumble strips. Denny Hamlin: "We need to run the course like it's designed to be run and right now you're just looking at areas you can cheat it -- the guys that cheat it run way faster. ... There was made to be a chicane to slow us down. [The change made] is going to make us respect that corner."