This ARP performance fastener, stud, bolt, tool, or assembly is the M12in 8740 Black Oxide 12-pt Nut Kit. Confirm the exact engine or vehicle application, thread size, length, material, strength series, included quantity, installation lubricant, tightening sequence, and current ARP torque specification before ordering.

Key Features

• 8740 Chrome Moly Steel: Provides 180,000 PSI tensile strength to withstand extreme torque and vibration in performance engines.
• Made from 8740 chrome moly steel with black oxide coating and 180,000 PSI tensile strength for high-horsepower builds.
• Black Oxide Finish: Guards against rust and corrosion for durability in harsh engine bay environments.
• Precision CNC machined for exact fit and repeatable performance.
• Designed for use with ARP rod bolts, head studs, and main studs only.
• Designed for ARP M12x1.25 bolts in Honda S2000 F-series, Subaru EJ20 EJ25, VW Audi 1.8T, and Mitsubishi Eagle Plymouth 4G63 engines.

Fitment

Specifications

What’s Included

One new ARP hardware kits – other in the exact configuration and quantity identified by this listing. Brackets, wiring, air lines, fittings, switches, fasteners, fitting kits, fluids, covers, and accessories are included only when expressly stated for this exact part.

About ARP

Automotive Racing Products manufactures high-performance studs, bolts, nuts, washers, wheel hardware, assembly tools, and installation lubricants for engine, drivetrain, chassis, and racing applications. Thread dimensions, material, preload method, lubricant, torque, and included quantity remain exact-part specific.

Important Disclosures

• California Proposition 65 warning applies. Review the current manufacturer warning before handling or installation.

Related Parts

• Shop all ARP products
• ARP .875in OD x 7/16in ID Insert Washers (10 pack)
• ARP 01-06 6.6L GM Duramax Diesel Flywheel Bolt Kit
• ARP 01-10 6.6L GM Duramax Diesel Flexplate Bolt Kit

Frequently Asked Questions

How do I confirm the M12in 8740 Black Oxide 12-pt Nut Kit fits my application?
Match the exact engine family or vehicle, component location, thread diameter and pitch, under-head length, material, strength series, and every current ARP application note.

Can I reuse the factory torque value with this ARP hardware?
Not automatically. Use ARP’s current instructions for the exact part, material, lubricant, tightening sequence, and preload method. Factory torque values may be based on different hardware and friction.

What is included with this ARP kit?
Only the studs, bolts, nuts, washers, lubricant, and tools expressly listed for this exact part number are included. Verify the required quantity before disassembly.

Installation Instructions

1. Confirm ARP part number 301-8318, the complete application, and every required supporting component before beginning work.
2. Clean and inspect all mating threads and components, then verify thread engagement, length, washers, nuts, lubricant, and required preparation before assembly.
3. Follow ARP’s current tightening sequence, lubricant instructions, torque or stretch method, and any retorque procedure for this exact part.
4. Verify clearance, preload, fastener seating, and normal component operation before returning the vehicle or engine to service.

This ARP performance fastener, stud, bolt, tool, or assembly is the M12in 8740 Black Oxide 12-pt Nut Kit. Confirm the exact engine or vehicle application, thread size, length, material, strength series, included quantity, installation lubricant, tightening sequence, and current ARP torque specification before ordering.

Key Features

• 8740 Chrome Moly Steel: Forged for 180,000 PSI tensile strength to withstand high cylinder pressures and boost levels.
• Kit includes 25 nuts made from premium 8740 chrome moly steel with 180,000 PSI rating and black oxide coating.
• 12-Point Design: Delivers 12 contact points for positive wrench grip and prevents fastener rounding during high-torque assembly.
• Black Oxide Finish: Provides corrosion resistance and reduced friction for smoother installation and long-term durability.
• Every nut forged heat-treated and machined to exacting tolerances.
• Made in USA with rigorous quality control for reliability in every build.

Fitment

Specifications

What’s Included

One new ARP hardware kits – other in the exact configuration and quantity identified by this listing. Brackets, wiring, air lines, fittings, switches, fasteners, fitting kits, fluids, covers, and accessories are included only when expressly stated for this exact part.

About ARP

Automotive Racing Products manufactures high-performance studs, bolts, nuts, washers, wheel hardware, assembly tools, and installation lubricants for engine, drivetrain, chassis, and racing applications. Thread dimensions, material, preload method, lubricant, torque, and included quantity remain exact-part specific.

Important Disclosures

• California Proposition 65 warning applies. Review the current manufacturer warning before handling or installation.

Related Parts

• Shop all ARP products
• ARP .875in OD x 7/16in ID Insert Washers (10 pack)
• ARP 01-06 6.6L GM Duramax Diesel Flywheel Bolt Kit
• ARP 01-10 6.6L GM Duramax Diesel Flexplate Bolt Kit

Frequently Asked Questions

How do I confirm the M12in 8740 Black Oxide 12-pt Nut Kit fits my application?
Match the exact engine family or vehicle, component location, thread diameter and pitch, under-head length, material, strength series, and every current ARP application note.

Can I reuse the factory torque value with this ARP hardware?
Not automatically. Use ARP’s current instructions for the exact part, material, lubricant, tightening sequence, and preload method. Factory torque values may be based on different hardware and friction.

What is included with this ARP kit?
Only the studs, bolts, nuts, washers, lubricant, and tools expressly listed for this exact part number are included. Verify the required quantity before disassembly.

Installation Instructions

1. Confirm ARP part number 301-8400, the complete application, and every required supporting component before beginning work.
2. Clean and inspect all mating threads and components, then verify thread engagement, length, washers, nuts, lubricant, and required preparation before assembly.
3. Follow ARP’s current tightening sequence, lubricant instructions, torque or stretch method, and any retorque procedure for this exact part.
4. Verify clearance, preload, fastener seating, and normal component operation before returning the vehicle or engine to service.