Dirt Logic 2.5 Coilovers. From our desert racing experience the Dirt Logic 2.5 has been developed for exceptional performance in a variety of Coilover applications. The Dirt Logic 2.5 will provide incredible dampening capacity for aggressive offroad driving. Features 2.5 OD Stainless Steel Body. 2.25 OD Billet Aluminum Piston. 78 NitroSteel Black Piston Rod. Cold Wound Coil Springs. Adjustable Coilover Construction. 58 Spherical Ball Mounting Ends. Extended Length - E28.13. Collasped Length - C22.27. Stroke Length - S5.86 . Top Mount - TP. Bottom Mount - BPF1.