SKU: 613-1250 | UPC: 672036015893
ARP 3/8in x 16 - 1.25in UHL 12pt SS Bolt Kit (5/pkg)
This ARP bolt kit includes five 3/8"-16 thread x 1.25" under head length stainless steel bolts with 12-point heads, built for demanding engine applications such as exhaust headers, valve covers, and rocker arms. These fasteners provide consistent clamp load and resistance to fatigue in high-heat high-vibration environments found in street and race engines. Ideal for builders seeking dependable hardware that holds up over thousands of cycles.
Key Features
- Stainless Steel Build: Resists corrosion and maintains strength in harsh engine bay conditions for extended service life
- 12-Point Head Design: Enables secure wrench engagement for accurate high-torque application without rounding
- Precision-Rolled Threads: Delivers maximum thread strength and consistent torque retention across repeated installations
- 1.25in Under Head Length: Matches common engine component thicknesses for flush secure fitment
- 5-Piece Kit: Complete matched set simplifies ordering and ensures uniform performance
Product Notes
- Confirm thread size length and pitch match your specific component before purchase
- Pair with ARP washers if application requires added load distribution
- Packed in protective packaging for damage-free arrival
Installation Notes
- Professional installation recommended.
- Clean mating surfaces and threads apply ARP Ultra-Torque lubricant as specified
- Torque in proper sequence to ARP values recheck after heat cycles
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Various | Performance Engines | Headers Valve Covers Rocker Arms |
| 1997-2013 | Chevrolet | Corvette Camaro | LS1 LS2 LS3 LS7 |
| 1969-1995 | Chevrolet | Small Block Engines | 350 383 Stroker Builds |
| 1996-2004 | Ford | Mustang | 4.6L Modular |
| 1970-1997 | Ford | Big Block Engines | 460 351W Headers |
Why Choose ARP?
- ARP sets the industry standard with fasteners proven in NHRA Top Fuel and NASCAR
- Every bolt undergoes rigorous testing for tensile strength and fatigue resistance
- US-made with exacting tolerances for repeatable results in pro engine builds
Frequently Asked Questions
-
Q: What applications do these bolts fit best?
A: Designed for exhaust headers valve covers rocker arm shafts and similar engine hardware requiring 3/8-16 x 1.25 UHL fasteners in GM Ford and other performance engines -
Q: What material and finish do they have?
A: Made from 300 series stainless steel with rolled threads for superior strength and natural corrosion-resistant finish -
Q: What torque specs should I follow?
A: Consult ARP installation sheet or application guide use Ultra-Torque lube and follow sequenced torque values typically 35-45 ft-lbs depending on component
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Compact protective box 4in x 3in x 1in
- Weight: 0.35 lbs
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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