ARP Main Stud Kit
2004–2006 Scion xA / xB 1NZFE Engine
203-5408
Overview:
The ARP 1NZFE Main Stud Kit is a premium upgrade designed specifically for the 2004 to 2006 Scion xA and xB models equipped with the 1NZFE engine. This kit replaces the factory main bearing bolts with high-strength ARP2000 studs, providing enhanced clamping force and durability under demanding conditions. Ideal for enthusiasts seeking improved engine reliability and performance, these studs ensure your engine’s bottom end remains secure during high-stress operation.
Whether you are rebuilding your engine, upgrading for increased power, or simply aiming for long-term durability, the ARP main stud kit offers a precision-engineered solution that outperforms standard hardware.
Key Features:
Engineered for strength, precision, and reliability, the ARP 1NZFE Main Stud Kit includes:
- Constructed from premium grade 8740 chromoly alloy, exceeding aircraft quality standards
- Heat-treated to an impressive 220,000 psi tensile strength for maximum durability
- Centerless ground for exceptional straightness and concentricity, ensuring perfect alignment
- Thread-rolled after heat treatment to increase fatigue strength by approximately 1000%
- Improved gasket and cylinder head alignment for easier assembly and enhanced sealing
- Designed specifically for the 1NZFE engine in Scion xA and xB models from 2004 to 2006
- Corrosion-resistant finish for long-lasting performance
- Manufactured to exacting tolerances for consistent, reliable fitment
Construction & Design:
ARP main studs are crafted from 8740 chromoly alloy, a high-strength steel alloy known for its toughness and resilience. This material is heat-treated to a tensile strength of 220,000 psi, providing superior clamping force compared to OEM bolts. The studs undergo a centerless grinding process, which involves multiple precise cuts to achieve near-perfect straightness and concentricity. This meticulous manufacturing process ensures that cylinder heads and gaskets fit flawlessly, reducing the risk of leaks and improving engine longevity.
Unlike standard bolts that are threaded before heat treatment, ARP studs are thread-rolled afterward. This process significantly enhances fatigue resistance, making these studs ideal for high-performance and high-stress applications. The result is a stud kit that delivers consistent clamping force and superior durability under extreme conditions.
Installation & Fitment:
The ARP 1NZFE Main Stud Kit is designed as a direct replacement for the factory main bearing bolts on 2004–2006 Scion xA and xB models with the 1NZFE engine. Installation requires standard engine disassembly procedures, and no modifications to the engine block or components are necessary. Due to the precise manufacturing tolerances, cylinder heads and gaskets will align smoothly during assembly, simplifying installation and reducing the risk of damage.
For best results, it is recommended to follow ARP’s installation guidelines and use the appropriate torque specifications and lubricants to ensure optimal clamping force and longevity.
What's Included:
- ARP2000 main studs for the 1NZFE engine
- Installation instructions
Ideal For:
This main stud kit is ideal for Scion xA and xB owners who are rebuilding their 1NZFE engine, upgrading for increased power output, or seeking enhanced engine durability and reliability. It is especially suited for enthusiasts involved in performance tuning, track use, or those who demand higher clamping strength than factory hardware can provide.
