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ARP 300-8303 12-Point Stainless Steel Cylinder Head Nut

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

300-8303
09/12/2036 6:48 AM
Sale Price

$3.58

In Stock (10+)

delivery box

Usually delivered within 2 days

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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 300-8303 is a precision-engineered 12-point cylinder head nut designed for high-performance engine applications. Constructed from ARP 300 Series stainless steel, this fastener delivers exceptional strength and corrosion resistance where it matters most.

Key Features:

  • 300 Series stainless steel construction for superior corrosion resistance
  • 12-point design for precise torque application and easier installation
  • Rated at 180,000 psi tensile strength for extreme durability
  • Polished to a brilliant luster for professional appearance
  • Engineered to meet ARP's stringent quality standards
  • Single piece design for reliable performance

ARP fasteners are the gold standard in the performance and racing industries, trusted by professional engine builders worldwide. This nut features ARP's precision manufacturing and quality control processes to ensure consistent clamping force and long-term reliability in demanding applications.

Products specifications

Fastener Yield Strength (psi)

150,000 psi

Nut Finish

Black oxide

Nut Material

Steel

Nut Style

12-point

Nylon Insert

No

Quantity

Sold individually.

Self-Locking

No

Size

7/16-20

Socket

1/2

Thread Size

7/16-20 RH in.

Washers Included

No

Wrench Diameter

1/2 in.

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