ARP 203-4301 Custom Age 625+ Head Stud Kit for 2JZ Engines
When you increase the power on your engine, you must upgrade the hardware holding down the head to prevent the head from lifting under extreme cylinder pressure. These are the newest technology from ARP. They offer even greater strength than the L19 but these will not have corrosion induced failure. L19 will snap in half if exposed to water, these will not! This is a recommended upgrade for the big boys running high boost 35psi+ and higher.
Custom Age 625 Plus®: This newly formulated super-alloy demonstrates superior fatigue cycle life, tensile strength and toughness – with complete resistance to atmospheric corrosion and oxidation. ARP is the first to develop manufacturing and testing processes for fasteners with Custom Age 625+. Best of all it is less expensive and expected to soon replace MP-35 as the material of choice in the high strength, super-alloy field. Typical tensile strength is 260,000-280,000 psi.
