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SKU: 301-8309
ARP M12 8740 Black Oxide 12-pt Nut Kit for Honda Civic Si Subaru WRX STI
ARP M12 8740 Black Oxide 12-pt Nut Kit delivers secure fastening for performance engine components like head studs. Fits M12x1.5 threaded applications in Honda K-series and Subaru EJ engines including Civic Si and WRX models. Built with 180,000 PSI tensile strength for reliable clamping under high boost and RPM.
Key Features
- 8740 Chrome Moly Steel: Forged construction rated at 180,000 PSI tensile strength to withstand extreme cylinder pressures and vibrations
- Black Oxide Finish: Resists corrosion and galling while allowing smooth torquing in engine bays
- 12-Point Head Design: Provides 12 contact points for positive grip using 19mm 12-point socket and better access around headers
- Thick Wall Profile: Maximizes rigidity and thread engagement without adding bulk for tight clearances
- 10 Nuts Per Kit: Complete set for cylinder head or main stud replacements on multi-cylinder engines
Product Notes
- Confirm M12x1.5 thread match with existing ARP studs before use
- Apply ARP thread lubricant during assembly for precise torque
- Packaged in protective tube to prevent damage during storage
Installation Notes
- Professional installation recommended.
- Torque to ARP specifications using calibrated torque wrench in sequence
- Direct replacement for OEM or stock nuts on ARP M12x1.5 studs
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2006-2011 | Honda | Civic | Si (K20Z3) |
| 2002-2006 | Acura | RSX | Type-S (K20A2) |
| 2004-2021 | Subaru | Impreza | WRX/STI (EJ25) |
| 2004-2009 | Subaru | Legacy | GT (EJ25) |
| 2004-2017 | Subaru | Forester | XT (EJ25) |
| 1999-2001 | Honda | Civic | Si (B16A2) |
Why Choose ARP?
- Trusted by NHRA and SCCA racers for decades in high-horsepower builds
- Every nut 100% inspected for thread accuracy and material integrity
- Precision CNC machined threads for consistent preload and sealing
Frequently Asked Questions
-
Q: What vehicles does this nut kit fit?
A: Designed for M12x1.5 ARP studs in Honda K20 B16 engines like Civic Si RSX and Subaru EJ25 in WRX STI Legacy GT Forester XT -
Q: What material and finish do these nuts have?
A: Made from 8740 chrome moly steel with black oxide coating for strength corrosion resistance and reduced friction -
Q: Is there a warranty on ARP nuts?
A: ARP provides lifetime warranty against defects in materials or workmanship when installed and used per instructions
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Secure plastic tube in 4in x 3in x 1in box
- Weight: 0.10 lbs
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