Step 1:
Create a new project, or assembly, and place two hinges of your choice, I like drive hinges.


Step 2:
Add some poles to hold your springs, the sizes don't have to be exact.


Step 3:
Add a spring on either side of the vertical poles, and on the inside of each of the poles that extend out.

Step 4:
Connect the springs, and tune them as you wish, I'd reccomend giving them a high force, around 7500-9000, so your springs can hold the weight of a car. Set the spread to 0, and make the length extend slightly past your end rods.

Step 5:
Test! Drive your car and see how it works, tune the settings until it's just right.

Step 6:
Drive!

Well now that you've read my guide, i'll give you a nice picture to look at.