I did a hard launch at stock stall speed w/ 2.73s a few days ago just practicing stuff a bit. I checked the marks, there were two lines that looked like:

= = = = = : :

Why did it make dotted lines like that? I didnt really try anything else just curious why they weren't straight lines that time.

 

Axel hop

 

As stated above, wheel hop. Do a search...common problem especially if you lower you car.

 

LCA's are the cheapest way to help eliminate that problem.