coil over

Question about the coilover conversion from torsion bars. I don't get that they say "All trucks, Superlifted or not, will require extended eyelets." But then say afterwards. "Do not use the extended eyelets if doing this conversion on a stock height Ranger. They will reduce your up travel and...

I've never set up a 4link suspension before and was wondering where is a good place to start? I plan in running coilovers in the back, but don't really know where to start when it comes to length of links? Or how far apart they should be mounted on axle and frame or is a triangulated 3 link...