CUTTING EDGE FASTENER TECHNOLOGY ARP head studs are a critical component for maximum reliability when building for power. A head stud ensures more accurate torque loading and consistent head gasket clamping forces. When compared to a traditional head bolt a smaller portion of the fastener torque is wasted in friction and fastener twist so more force can be applied toward sealing the head gasket. Head gasket sealing is more often than not the Achillies heal of building for power. Increased combustion pressures will try to lift the head and reduce the sealing effectiveness of the gasket. All ARP head studs are centerless ground for concentricity with cold rolled threads for maximum fatigue strength. ARP2000 alloy has a 220ksi tensile strength. The EJ studs are undercut to more effectively compensate for head gasket compression. The FA studs are not undercut to maximize strength. EJ and FA head studs are the same length and thread size making them effectively interchangeable. All head studs feature a broached allen hex in the end of the stud for easy installation. 11mm is the factory thread size so no machine work is required, and they are a direct replacement for the factory head bolts. It is essential to follow the supplied instructions and use the included ARP thread lubricant. Use only an accurate torque wrench of known calibration to ensure best results. Any fastener "spring back" detected at any point during the torque process will require the washer to head surfaces to be meticulously cleaned and the stud re-torqued in order to achieve accurate torque values. Manufacturer Part Nos. 260-4701 (EJ), 260-4302 (FA) What it fits: EJ DOHC FA20/FA24
