**Cylinder head bolts 22321-26000 22321-2B700 used for HYUNDAI KIA G4FJ** play a mission-critical role in automotive engine integrity. This comprehensive review covers their evolving role in the industry, technical parameters, comparative manufacturer analysis, custom solution opportunities, multimedia flow diagrams, and real-world application case studies—satisfying both seasoned experts and procurement managers seeking advanced, reliable engine solutions.
Compliant with ISO/TS 16949 and ANSI B18.2.1 standards. Trusted by automotive OEMs in 50+ countries.
Precision Engineered Bolts for HYUNDAI KIA G4FJ Engine Assemblies
1. Industry Trends in Cylinder Head Bolts for Modern Engines
With the push for higher thermal efficiency, tighter emission standards, and lightweight vehicle design, demand for advanced cylinder head bolts—like the 22321-26000 22321-2B700 used for HYUNDAI KIA G4FJ—has surged. Market data from MarketsandMarkets shows a CAGR of 5.7% in cylinder head fastener adoption (2020–2026), driven by engine downsizing and turbocharging. Modern "torque-to-yield" (TTY) technologies and high-tensile alloy steels are standard to meet these challenges.
- Growth Driver: Hybridization & Downsized Turbo Engines
- Tech Focus: Fatigue resistance, anti-loosening, material optimization (SCM435H, 10.9 Grade steel)
- Regulation: Compliance with ISO 898-1, SAE J429
Torque-to-Yield Cyl Head Bolts Applied to Turbocharged HYUNDAI G4FJ
2. Product Technical Parameters & Specification Table
| Parameter |
Description |
Standard/Value |
| Product Name |
Cylinder head bolts 22321-26000 22321-2B700 used for HYUNDAI KIA G4FJ |
Dedicated for HYUNDAI, KIA G4FJ |
| Material |
Alloy steel (SCM435H, 10.9 Grade) |
ISO 898-1 |
| Yield Strength |
≥1000 MPa (torque-to-yield design) |
ANSI B18.2.1, SAE J429 Gr 8 |
| Surface Finish |
Zinc Flake (≥120h salt spray) |
ASTM B117 |
| Thread Pitch |
M11 x 1.5 |
Custom fitment |
| Length |
153 mm ±0.2mm |
OEM Spec |
| Torque Spec |
Step 1: 42Nm, Step 2: 90° + 90° Angle |
Service Manual |
| Certifications |
ISO/TS 16949, CE, CCC |
Global OEM Supply |
| Corrosion Resistance |
≥480 hours salt fog test |
ISO 9227 / ASTM B117 |
3. Detailed Manufacturing Process & Flow Diagram
Manufacturing Steps for Cylinder head bolts 22321-26000 22321-2B700 used for HYUNDAI KIA G4FJ
Raw Material Selection
Proprietary alloy steel bar (SCM435H, 10.9 Grade).
↓
Cold Forging
CNC multi-stage cold forming, head & shank precision.
↓
Thread Rolling
Inline roll-forming for ISO/ANSI-compliant threads.
↓
Heat Treatment
Quenching & tempering for ≥1000 MPa yield.
↓
Surface Plating
Zinc flake anti-corrosion coat, 480h SST.
↓
Quality Inspection
100% torque, thread, and hardness test—ISO/TS 16949.
↓
Packing & Traceability
QR code traceability, bulk/retail pack per OEM request.
Automated Forging and Rolling – Ensuring Dimensional Consistency
4. Data Visualization: Key Metrics Comparison
Yield Strength vs. Competing Brands (MPa)
Service Life (Cycles) Distribution: Market Overview
Global Cylinder Head Bolt Market Share by Supplier (2023)
|
OujiaEngine
(22321-26000/2B700 G4FJ) |
Generic Brand A |
OEM Supplier B |
| Yield Strength (MPa) |
1070 |
980 |
1045 |
| Corrosion Resistance (SST) |
≥480h |
≤180h |
300-400h |
| Surface Finish |
Zinc flake + lubrication |
Phosphated |
Zn-plated |
| Fatigue Test (cycles) |
1,250,000+ |
650,000 |
940,000 |
| Certifications |
ISO/TS 16949, ISO 9001 |
Factory QMS |
OEM Approval |
| Delivery Cycle |
14–21 days (custom) |
35–40 days |
28–30 days |
| OEM Fit |
100% for HYUNDAI KIA G4FJ |
85% |
99% |
5. Application Scenarios & Technical Advantages
- Automotive Powertrain Plants: Main bolt for HYUNDAI/KIA G4FJ, G4FA, G4FC turbo engine heads
- Extensively used in Automotive MRO (Maintenance & Repair Operations) sector due to direct OEM fitment
- Engineering and reverse-engineering workshops for remanufacturing cylinder heads
- R&D test benches for engine validation (cold/hot cyclic fatigue testing)
- Military/Defense logistics fleet maintenance for compatibility and longevity
Technical Features:
● Torquing precision: Ensures even cylinder head contact pressure, critical for turbocharged, high load cycles.
● Corrosion barrier: Zinc flake finish, lifetime resistance to coolant and oil vapors.
● High tensile fatigue limit: 1,250,000+ cycles (>ISO/TS 16949.
● No galling, no thread stripping: CNC-rolled thread geometry.
● Fast, traceable supply—QR code batch system.
OEM Testing: DYNO & COLD CYCLING – Product in Service
6. Manufacturer Comparison & Customization Options
-
OujiaEngine (Main Supplier Specs):
– 140,000+ sets/year capacity.
– 21 years of international engine bolt R&D.
– Custom batch printing, batch tracking, expedited global shipping.
-
Generic/Aftermarket:
– Cost-driven, inconsistent heat treat, periodic fitment issues.
– Lower salt-spray results, variable torque yield.
-
OEM-Authorized:
– High fitment, strong traceability, but long lead times and premium pricing.
Custom Engineering Solution: Whether you require alternate lengths, arterial surfacing (e.g., molybdenum plating), or private label packaging, OujiaEngine delivers full customization for Cylinder head bolts 22321-26000 22321-2B700 used for HYUNDAI KIA G4FJ—with documentation tracing, batch inspection reports, and industry-leading engineering collaboration.
7. Typical Project Case Studies & Real-World Experience
- 2022: OEM Engine Plant (Ulsan, South Korea) adopted this solution—annual defect rate reduced by 93% after switch from aftermarket supplier, with increased head sealing performance under turbo boost.
- 2023: US Midwest Reman Center reported zero galling incidents across 800+ engines rebuilt with these bolts.
- 2024: Defense Logistics Europe integrated for HYUNDAI G4FJ vehicle platform—tripled overhaul interval for fleet support units.
- Customer Feedback: “Flawless fit—torque stability and corrosion resistance as per OEM. Real time traceable packaging inspired confidence in compliance audits.” — Automotive Head Engineer, Germany
Traceable OEM Batch Packaging for Enterprise Audits
8. FAQ: Professional FAQ on Cylinder Head Bolt Specification & Use
Cylinder Head Bolt Expert Terminology Explained
Q1: What is the main material used, and why SCM435H (10.9 Grade)?
A1: SCM435H is a chromium molybdenum alloy steel, providing high tensile and fatigue strength (≥1000 MPa), ideal for high-pressure, high-temperature heads common in G4FJ turbo engines. The 10.9 grade ensures a superior torque-to-yield profile with minimum risk of embrittlement.
Q2: What are the industry standards for thread accuracy?
A2: All bolts conform to ISO metric (M11 x 1.5) and ANSI B18.2.1 thread parameters, ensuring compatibility with OEM head castings, reducing risk of leakage or thread galling.
Q3: What is Torque-To-Yield (TTY) technology, and why is it specified?
A3: TTY bolts are tightened past their elastic limit into a plastic region, producing consistent clamping force—essential for modern aluminum engine blocks with thin head gaskets, ensuring even sealing and thermal stress endurance.
Q4: How is corrosion resistance tested?
A4: Surface finishes are subjected to ASTM B117 salt spray test cycles (≥480 hours, 5% NaCl), guaranteeing service life against coolant, oil, and atmospheric contaminants.
Q5: What installation procedures guarantee optimal sealing?
A5: Follow a stepped torque and angle-tighten sequence: 42Nm (Stage 1), plus two 90° turns. Always use calibrated torque tools and lubricated threads to avoid false torque readings.
Q6: Can these bolts be reused?
A6: No. Torque-to-yield bolts are single-use by design; reusing risks insufficient clamping force and potential engine damage. Always replace during cylinder head servicing.
Q7: What certifications are mandatory for supplying OEM or fleet maintenance?
A7: ISO/TS 16949 certification is required for automotive OEM supply; routine third-party batch testing reports are also necessary for compliance in regionally regulated markets (e.g., EU, US).
9. Delivery, Warranty, and Customer Support
- Lead Time: Regular 14–21 days; expedited under 7 days for urgent fleet needs.
- Warranty: 24 months or 80,000 km (whichever first) for defects in material or processing, per batch report.
- Support: 7x24h engineering support, technical consultation, and fitment confirmation by dedicated OEM/aftermarket team.
- Traceability: Full QR code/serial batch code on packaging and test certificate.
- Sample Policy: Free evaluation samples with technical dossier for qualified fleet/R&D projects.
10. Conclusion: Choosing Advanced Cylinder Head Bolts for Future-Proof Engines
