ARP Head Stud Kit Nissan RB25DE / RB25DET

ARP head stud kit for Nissan 2.5L 24v inline-6 RB25DE (naturally aspirated) and RB25DET (turbo) engines. Available in 2 material grades to suit different engine build levels.

Common technical specifications

• Manufacturer: ARP (Automotive Racing Products)
• Origin: Made in USA (Santa Paula and Ventura, California)
• Type: Head stud kit
• Application: Nissan RB25DE and RB25DET
• Manufacturer certifications: ISO 9001 and AS9100
• Packaging: Complete kit for 1 Nissan RB25 cylinder head

Kit contents

• Head studs
• Nuts
• Hardened washers

Available part numbers

• 202-4301 (ARP8740): 8740 chromoly steel, tensile strength 200,000 psi (1379 MPa). ARP's proven standard grade.
• 202-4309 (ARP2000): molybdenum-vanadium steel, tensile strength 220,000 psi (1517 MPa). High performance grade recommended for motorsport applications.

Material selection

The choice of grade depends on the engine build level and application:

• ARP8740 (202-4301): recommended for naturally aspirated RB25DE or RB25DET in near-stock configuration (moderate boost). Cost-effective and proven solution for street and moderate performance applications.
• ARP2000 (202-4309): recommended for highly built RB25DET engines (high boost, drag, circuit). The higher 220,000 psi tensile strength provides a better safety margin against head lift under high pressure.

ARP process

ARP studs are forged from high strength materials, machined on precision CNC centres and individually heat treated. Each stud is inspected to ensure compliance with ARP's aerospace specifications.

Application

Compatible with Nissan 2.5L 24v inline-6 engine:

• Nissan RB25DE (naturally aspirated)
• Nissan RB25DET (turbo, all versions: S1, S2 and NEO)

Important: use exclusively with ARP Ultra-Torque lubricant (part 100-9904) to ensure correct preload. Strictly follow the torque sequence and values provided in the ARP instructions included with the kit. Use of an ARP stretch gauge is strongly recommended for the most demanding applications.