Yes, I found your project. Traxxas Tan and Black is a joke to me (; I had to use blue and purple (5.5 and 6.4). At the end I ordered a more stiff spring than purple.
The number is smaller. In my hand it feels stiffer. Video 1-7 is with long travel rockers, this makes it extremly "weak?" .
greets titan
PS I will add the sway bar in the rear and make a video. Ohh I should preorder alu rockers to hold the stress...