Lamspeed Racing's customised ARP Custom Age 625+ Head Stud kit for the Nissan SR20DET engine utilises ARP's newly formulated super-alloy - Custom Age 625+, and features Dog Point bottoms.
Dog Point Feature
A Dog Point is a straight pointed section, reduced in diameter slightly below the root diameter of the thread. It usually extends in length about two-thirds the diameter of the thread. This aids component assembly, seats studs in the block, and preloads the fastener for accurate, repeatable torque sequencing.
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.
- a set of ten Custom Age 625+® head studs with Dog Points,
- ten parallel ground washers,
- ten 8740 chrome moly steel 12pt nuts, and
- a 1/2 oz. pack of ARP Ultra-Torque fastener assembly lubricant.
All Custom Age 625+® studs are centerless ground, heat treated prior to thread rolling and machining, and are nominally rated at 270,000 psi.
These fasteners deliver a 55% increase in tensile strength over the OEM Torque to Yield (TTY) head bolts.