Automotive fasteners engineered for high clamp strength and corrosion resistance. Secure fixing brings reassurance during maintenance and high-stress builds. Are ARP Stainless Steel Bolts the right choice for demanding engine work?
⚡ At a Glance
- • Tensile Strength: Rated at 170,000 PSI, far above typical Grade 8 fasteners
- • Best for: High-stress engine assemblies and performance applications requiring strong clamp loads
- • Not ideal for: Applications that require metric threads or non-12-point head configurations
Polished Stainless 300 alloy bolts, 5/16-18 thread and 1.250in under-head length. Compact 12-point heads with 3/8in wrenching and a 170,000 PSI rating suit heavy-duty automotive use.
High clamp reliability - thanks to 170,000 PSI tensile rating
A tensile rating of 170,000 PSI denotes the maximum tensile stress the fastener can withstand before failure, expressed as pounds per square inch. That rating signals substantially higher strength than common Grade 8 hardware.
Greater allowable load reduces risk of bolt stretch or failure under heavy clamping, improving durability in stressed assemblies.
Long-term corrosion resistance - with polished Stainless 300 alloy
Polished Stainless 300 is a proprietary stainless steel alloy described as impervious to rust and corrosion in the product information. The polished finish helps resist surface oxidation.
Suitability for damp or corrosive environments lowers maintenance frequency and keeps fastener integrity over time.
Easier access in tight spaces - with compact 12-point heads and 3/8in wrenching
Compact 12-point heads reduce clearance needed for tool engagement, while 3/8in wrenching indicates the common drive size for tightening. Under-head length is specified at 1.250in for predictable thread engagement.
Compact head form and standard drive size make fastening and removal simpler in crowded engine bays and assemblies.
✨ The 4 Key Reasons for ARP Stainless Steel Bolts
- Under-head length 1.250in - Provides consistent thread engagement in shallow flange fittings
- 3/8in wrenching - Allows use of common drive tools for compact tightening operations
- Compact 12-point heads - Fit into tighter spaces than standard hex heads
- Pack of five - Keeps spare fasteners ready for maintenance or assembly tasks
📋 Technical Details at a Glance
- Category: Automotive Parts and Accessories
- Brand: ARP
- Material: Polished Stainless 300
- Thread size: 5/16"-18
- Thread pitch: 18 threads per inch
❓ Frequently Asked Questions
Q: Are these bolts corrosion-resistant?
A: Manufactured from polished Stainless 300 steel, described as a proprietary alloy impervious to rust and corrosion.
Q: What size and thread are the bolts?
A: Diameter is 5/16" with a standard 18 threads per inch pitch, specified as 5/16-18.
Q: What head type and wrench size do they use?
A: Heads are compact 12-point style and wrenching is 3/8in, with an under-head length of 1.250in.
🏆 Our Verdict
ARB-grade hardware aimed at enthusiasts and professionals who need high-strength, corrosion-resistant fasteners for engine and performance applications. The polished Stainless 300 construction paired with a 170,000 PSI tensile rating and compact 12-point heads makes these bolts well suited to demanding builds. Higher initial outlay can be offset by reduced replacement and maintenance over the long term.
