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 2.5in OD Stainless Steel Body. 2.25in OD Billet Aluminum Piston. 78in NitroSteel Black Piston Rod. Cold Wound Coil Springs. Adjustable Coilover Construction. 58in Spherical Ball Mounting Ends. Extended Length - E28.65. Collasped Length - C23.55. Stroke Length - S5.10 . Top Mount - TP. Bottom Mount - B1.