Complete Frame Kit. This kit consists of the lower flat subframe connectors, upper subframe connectors and bulkhead stiffeners. The upper and lower subframe connectors are then tied together. Chassis bending (torsional twist) is reduced as much as 1,500 percent. These are almost mandatory for convertibles and are highly recommended for coupes. 94+ Street driven Mustangs with power seats may have to switch to a manual adjuster or modify the driver’s side upper rail.
Lower Flat Subframe Connectors. These are an absolute minimum. They connect the front and rear subframe.
Upper Subframe Connectors. These work in conjunction with the lower subframe connectors to form a much more rigid chassis. Large gains in rigidity are possible due to being tall in a vertical plane. Think of this like the floor joists in a house. You could try a zillion 2x4 under the floor, but if they were only four inches deep, the floor would never be rigid. Yet, a few 2x12’s make an incredibly rigid floor because of their deep vertical span. You can order the Upper and Lower Flat Subframe Connectors together in our full frame kit.