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ARP 155-3603 High Performance Cylinder Head Bolt Kit 8740 Chrome Moly

Manufacturer

ARP

<h3>About ARP – Automotive Racing Products</h3><p>Few names carry as much weight in the performance fastener world as <strong>ARP</strong> — short for Automotive Racing Products. Back in 1968, racing enthusiast Gary Holzapfel noticed that many of his friends' broken engines were caused by fastener failure, and at the time no commercially available studs or bolts were up to the challenge — so he drew on his years of experience as a leading aerospace subcontractor and founded ARP. That problem-solving spirit has driven the company ever since.</p><p>From a backyard garage workshop, ARP has grown into a highly diversified manufacturer with 18 buildings across Southern California, totaling more than 275,000 square feet of forging, heat-treating, machining, quality control, finishing, and packaging facilities in Santa Paula and Ventura, California.</p><h3>Engineering That Goes Beyond &quot;Aerospace Quality&quot;</h3><p>ARP uses only top-quality materials — far above the usual &quot;aerospace quality&quot; others settle for — in a highly exacting manufacturing process to create fasteners with the strength and durability to last race after race. Fastener materials are available in 8740 Chrome Moly, ARP2000, and Custom Age 625+, each engineered for specific performance thresholds. In order to ensure optimum quality control, ARP controls all aspects of the manufacturing process entirely in-house — a discipline that has allowed it to build a reputation for &quot;zero defects&quot; quality throughout the industry.</p><p>Automotive Racing Products has achieved ISO 9001:2008 and AS9100 registration, certifications the company has maintained as a testament to its unwavering dedication to producing the highest quality fasteners available. ARP also operates an Aerospace Division and is one of the very few companies in the world fully licensed by the United States Government to manufacture MS-21250 fatigue-rated fasteners.</p><h3>Trusted by the World&apos;s Top Racing Programs</h3><p>ARP enjoys working relationships with professional engine builders and race teams across Formula 1, IndyCar, IMSA, NASCAR, NHRA, IHRA, Lucas Oil Late Model Dirt, and World of Outlaws — constant interaction that keeps ARP on the cutting edge of fastener technology. Whether you&apos;re building a weekend bracket racer or a full-time professional race engine, ARP has a solution engineered to hold things together under the most extreme conditions.</p><h3>ARP&apos;s Engine Fastener Lineup</h3><p>Today, ARP&apos;s product line contains thousands of part numbers and has expanded to include virtually every fastener found in an engine and driveline and throughout the suspension and frame. Among the most popular are <a href="/48-arp-engine-cylinder-head-bolt-set-10306">Engine Cylinder Head Bolt Sets</a>, <a href="/48-arp-engine-connecting-rod-bolt-5280">Engine Connecting Rod Bolts</a>, and complete <a href="/48-arp-engine-connecting-rod-5276">Engine Connecting Rods</a> — three categories that represent the critical fastening points where engine integrity is made or lost. ARP&apos;s High Performance series head bolt kits are rated at 170,000 psi — 15 percent stronger than Grade 8 fasteners — and are available with hex heads or reduced-wrenching 12-point heads that eliminate the need for valvetrain removal when re-torquing.</p><p>ARP stands behind its products indefinitely with respect to materials and workmanship, making every fastener a long-term investment in engine reliability rather than a consumable component.</p>

Part Number

155-3603
09/11/2036 10:57 PM
Sale Price

$163.81

In Stock (10+)

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The ARP 155-3603 High Performance Series cylinder head bolt kit delivers professional-grade fastening strength for demanding engine applications. Manufactured from premium 8740 chrome moly steel and heat-treated to 180,000 psi tensile strength?15% stronger than Grade 8 fasteners?these head bolts provide superior clamping force and durability for high-performance and racing engines.

Key Features:

  • Premium 8740 chrome moly steel construction for exceptional strength and fatigue resistance
  • Heat-treated to 180,000 psi tensile strength, exceeding Grade 8 specifications
  • Hex head design with wide area flange eliminates need for valve train removal during retorquing
  • Includes hardened parallel-ground washers for even load distribution and accurate torque readings
  • Thread rolled after heat treatment for superior fatigue life and thread integrity
  • Precision manufactured to exacting tolerances for perfect cylinder head alignment

Manufacturing Excellence:

ARP's advanced manufacturing process ensures each fastener meets the highest quality standards. Head bolts are cold-forged to maintain molecular integrity, vertically rack heat-treated for complete penetration, and precisely machined to ensure concentricity. The thread rolling process occurs after heat treatment?a costly but critical step that provides approximately ten times better fatigue strength compared to pre-heat-treat threading methods used by other manufacturers.

Installation Notes:

The flanged hex head design allows for convenient cylinder head retorquing without removing valve train components, making maintenance faster and easier. Because head gaskets compress during initial torquing, always re-torque fasteners after the engine has been run to ensure optimal clamping force and seal integrity.

This kit is designed for engine builders who demand zero-defect reliability and maximum performance from their fastening systems. Each component is manufactured to ARP's exacting standards, ensuring proper gasket compression, consistent clamping force, and long-term durability in high-stress applications.

Products specifications

Cut to Fit

No

Fastener Finish

Black oxide

Fastener Material

Chromemoly

Fastener Style

Bolt

Head Style

Hex

Quantity

Sold as a kit.

Washers Included

Yes

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