The wireframe-shape is very thin. It's formed of lines between the defined points, and there's no radius-option.
With a radius-option it would be possible to make matching bounding shapes for poles, now a pole with wireframe-shape goes partially through the ground, depending how thick the pole is.
Thin poles don't seem to go through the ground much, but columns aren't very good target for wireframe-shape, because you clearly see how thin the wireframe is when half of the column is sinked to the ground.
Anyway, wireframe isn't only lines. First you define the co-ords of the points. Your car will collide with these tiny points.
The next step probably is to form lines between the points. Change the "Number of lines" to desired number.
But here are the lines:
4 // Number of points
0.0 , 0.0 , 0.0 // Coordinates of the point #0
0.0 , 0.1 , 0.0 // Coordinates of the point #1
0.5 , 0.1 , 0.0 // Coordinates of the point #2
0.5 , 0.6 , 0.0 // Coordinates of the point #3
3 // Number of lines.
0 , 1 // Create a line from point 0 to 1. (A)
1 , 2 // Create a line from point 1 to 2. (B)
2 , 3 // Create a line from point 2 to 3. (C)