Precision Fasteners Built for High Stress Automotive Applications
The ARP 644-1000 12-point bolt set delivers the strength and consistency needed for critical automotive fastening applications. ARP644-1000 measures 3/8in-16 thread by 1.000in length with a 7/16in 12-point wrenching head, finished in durable black oxide. Each package includes 5 bolts, making ARP644-1000 a practical choice for engine building, suspension work, and other performance fastening needs where a stock bolt is not strong enough.
Key Features
- 3/8in-16 thread, 1.000in length
- 12-point wrenching head design
- Black oxide finish for corrosion resistance
- Set of 5 bolts per package
- Manufactured to ARP's high strength standards
Specifications
| Detail | Value |
|---|---|
| MPN | 644-1000 |
| Thread Size | 3/8in-16 |
| Length | 1.000in |
| Wrenching | 12-Point, 7/16in |
| Finish | Black Oxide |
| Quantity | 5 Bolts |
What's Included
- Five ARP644-1000 12-point bolts
About ARP
ARP manufactures premium fasteners for racing and performance applications, producing bolts and studs engineered to handle the stress of high performance engines and drivetrains.
FAQ
What is the ARP644-1000?The ARP644-1000 is a set of 5 ARP 3/8in-16 x 1.000in 12-point black oxide bolts designed for high stress automotive applications.
What thread size is ARP644-1000?ARP644-1000 uses a 3/8in-16 thread pitch.
How long is ARP644-1000?ARP644-1000 measures 1.000 inch in length.
How many bolts come in a package of ARP644-1000?ARP644-1000 includes 5 bolts per package.
What wrenching size does ARP644-1000 use?ARP644-1000 uses a 7/16in 12-point wrenching head.
What finish does ARP644-1000 have?ARP644-1000 has a black oxide finish for improved corrosion resistance.
What applications is ARP644-1000 used for?ARP644-1000 is commonly used in engine building, suspension work, and other performance fastening applications.
Are ARP644-1000 bolts reusable?ARP recommends inspecting fasteners like ARP644-1000 for stretch or damage before reuse in critical applications.
Install Instructions
- Clean and inspect the threaded bore before installation
- Apply ARP thread lubricant to ARP644-1000 threads
- Thread ARP644-1000 into position by hand to start
- Torque ARP644-1000 to the specification required for your application
- Verify proper torque with a calibrated torque wrench
ARP
ARP (Automotive Racing Products) is the world’s premier manufacturer of high-strength engine and driveline fasteners—head studs and bolts, main studs, rod bolts, and more—engineered and manufactured in-house from start to finish for race-proven reliability. With vertically integrated processes that include cold heading, machining, heat-treating, thread rolling after heat treat, and rigorous QA, ARP maintains aerospace-level certifications (ISO 9001 and AS9100) and validates every part for repeatable clamp load and fatigue resistance. Signature alloys such as 8740 chromoly, ARP2000, L19, and Custom Age 625+ deliver ultimate tensile strengths up to the super-alloy range, while ARP Ultra-Torque fastener assembly lubricant helps achieve consistent pre-load during installation. From street performance builds to professional motorsport programs, ARP fasteners provide precise fitment, superior metallurgy, and the durability needed to keep engines together at elevated cylinder pressures and...
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