Fits 2004-2014 Subaru WRX STI.

Standard stamped-steel clutch forks are a known weak point in the Subaru drivetrain, especially when upgrading to heavy-duty performance pressure plates. The Comp1 Clutch Hydraulic Conversion Kit addresses this vulnerability by replacing the factory assembly with a high-strength forged fork and the necessary hydraulic components to ensure reliable actuation under high-load conditions.

By switching to a forged fork, you eliminate the risk of the fork bending or snapping during aggressive shifts or high-pressure engagement. This kit provides a more consistent pedal feel and ensures your clutch system can handle the increased clamping force of aftermarket performance clutches. It is a direct-fit solution designed to bolt into the factory location while offering the durability required for track use and high-horsepower street builds.

• Includes heavy-duty forged clutch fork to prevent flex and failure
• Complete hydraulic conversion hardware for seamless installation
• Compatible with factory and performance aftermarket clutch setups
• Engineered for 2004-2014 Subaru WRX STI (6-speed)

Fits select Mitsubishi applications utilizing a 1" x 23-spline transmission input shaft.

This Competition Clutch telescoped lower hub is a precision-engineered replacement component designed for high-performance multi-disc clutch assemblies. The telescoped configuration provides the specific offset and engagement depth required for proper stack height and alignment in racing clutch setups. Built to withstand the rigors of high-torque drivetrains, this hub ensures a positive mechanical connection between the friction discs and the input shaft, maintaining drivetrain integrity during aggressive shifts and heavy launches.

• Brand: Competition Clutch
• Hub Type: Telescoped / Lower Hub
• Spline Count: 23-Spline
• Input Shaft Diameter: 1.000"
• Application: Mitsubishi Drivetrains

This ARP replacement 12-point nut provides the high-strength fastening required for critical automotive assemblies. The 12-point head design offers more surface area for tool engagement than a traditional hex, allowing for easier access in tight clearances and more precise torque application without the risk of rounding off corners.

• Thread Size: M12 x 1.25
• Head Style: 12-Point
• Application: Replacement fastener
• Quantity: Single (1 Nut)

Machined to ARP's exact standards for thread accuracy and consistency, this nut is ideal for engine, drivetrain, or suspension builds where hardware integrity is a priority. Use this individual nut to replace lost hardware or to complete a custom high-performance fastener setup.

This ARP specialty stud provides a high-strength fastening solution for custom automotive applications requiring dual thread pitches. Measuring 7.300 inches in overall length, this stud features M12-1.25 threads on one end and M12-1.75 threads on the other, allowing for specialized transitions or mounting requirements in engine, drivetrain, or chassis assemblies.

• Precision-engineered by ARP for superior tensile strength and reliability
• Dual-thread design: M12-1.25 and M12-1.75 pitches
• Overall Length (OAL): 7.300 inches
• Threads are rolled after heat-treatment for optimum fatigue strength
• Designed to provide consistent clamping force for custom fabrication and mechanical repairs

This ARP specialty stud provides a high-strength fastening solution for custom automotive applications requiring dual-thread pitches. Manufactured from ARP's signature high-tensile alloy, this stud is designed to withstand significant stress and thermal cycles without stretching or failing.

The stud features a 7.250-inch overall length (OAL) with M12-1.5 threads on one end and M12-1.25 threads on the other. A key feature is the broached tip, which allows for a hex key or similar tool to be used for precise seating and installation in tight spaces where traditional methods are difficult. This ensures the stud is fully bottomed out and properly torqued into the mounting surface.

• Manufacturer: ARP
• Thread A: M12 x 1.5
• Thread B: M12 x 1.25
• Overall Length: 7.250 inches
• Feature: Broached tip for easy installation and removal
• Quantity: Sold individually (Single)

This single ARP Custom Age 625+ stud is engineered for extreme-duty applications where standard 8740 chromoly or even L19 hardware fails to meet the required tensile strength. Custom Age 625+ is a high-performance super-alloy that offers superior fatigue life and exceptional resistance to atmospheric corrosion and stress corrosion cracking.

Ideally used for custom engine builds or as a replacement stud, this fastener features precision-rolled threads applied after heat treatment to ensure maximum integrity and strength under high-clamping loads. The M12-1.25 thread pitch and 6.875-inch overall length make it a critical component for specialized high-boost or high-compression configurations.

• Material: Custom Age 625+ Super-Alloy
• Thread Size: M12 x 1.25
• Overall Length (OAL): 6.875 inches
• Configuration: Single Stud
• Manufacturing: Centerless ground and thread-rolled after heat treat

Fits Cummins 24V and select 2002 BMW 318i and 320i engines.

This ARP individual head stud provides the critical clamping force needed to maintain a reliable cylinder head seal under high load. Professional engine builders rely on ARP fasteners to replace factory head bolts that can stretch or yield, which often leads to head gasket failure in turbocharged or high-compression applications. Each stud is precision-machined and heat-treated to ensure consistent tension across the head surface, making it an essential component for high-performance builds or replacing a single damaged fastener.

• Brand: ARP
• Part Type: Individual Head Stud
• Engine Compatibility: Cummins 24V
• Vehicle Compatibility: 2002 BMW 318i / 320i
• Construction: High-strength heat-treated alloy
• Application: Replaces or supplements individual head fastener sets
• Function: Maintains cylinder head seal under extreme combustion pressure

Secure your engine's top end with a genuine ARP replacement single cylinder head stud for Cummins diesel engines. Whether you are replacing a single damaged fastener or completing a set, this individual stud provides the same high-tensile strength and precision engineering found in ARP's full head stud kits. Designed to provide superior clamping force compared to factory torque-to-yield bolts, these fasteners are critical for maintaining a reliable head gasket seal under high boost and increased cylinder pressures.

• Individual replacement stud for Cummins diesel applications
• Manufactured from high-strength, heat-treated alloys
• Precision-machined with rolled threads for maximum fatigue life and load distribution
• Provides consistent clamping force to prevent head gasket lifting
• Direct replacement for fasteners found in ARP Cummins head stud series

This heavy-duty single stud from ARP is engineered for high-stress automotive applications where fastener integrity is critical. Manufactured from ARP 2000 material, this stud offers superior tensile strength compared to standard hardware, making it an ideal choice for custom engine builds, drivetrain assembly, or specialized chassis components.

• Material: ARP 2000 Alloy
• Thread Pitch A: M12 x 1.5
• Thread Pitch B: M12 x 1.25
• Overall Length (OAL): 5.600 inches
• Fastener Style: Single Stud

Precision-machined to exacting tolerances, this stud ensures consistent clamping force and reliable thread engagement. Whether you are replacing a damaged fastener or sourcing components for a unique performance build, ARP's manufacturing process delivers the fatigue life and strength required for demanding environments.

This ARP M12 x 1.75 undercut stud is engineered to provide superior clamping force and consistent fastener stretch in high-performance applications. The undercut (U/C) shank design ensures the stud stretches more uniformly along its length, which is critical for maintaining accurate torque loads under extreme thermal stress and vibration.

• Thread Size: M12 x 1.75
• Shank Style: Undercut (U/C)
• Overall Length: 5.400 inches
• Thread Length: 1.250 inches
• Precision machined for high-strength reliability
• Manufactured by ARP (Automotive Racing Products)

This ARP high-strength stud is engineered for precision and durability in demanding automotive applications. Manufactured from premium materials and heat-treated for maximum fatigue resistance, it provides the consistent clamping force required for high-stress environments. This fastener is a reliable solution for custom assemblies where standard hardware lacks the necessary tensile strength or specific dimensions.

• Brand: ARP
• Thread Size: M12 x 1.25
• Overall Length: 4.950 in.
• Thread Length: 1.175 in.
• Fastener Style: Stud

This ARP M12-1.75 stud is engineered to provide superior clamping force and reliability for high-performance automotive applications. Built to handle the extreme stresses that standard hardware cannot, this stud ensures precise alignment and consistent torque loading for critical components.

• Thread Size: M12 x 1.75
• Underhead Length (U/C): 4.91 inches
• Secondary Dimension: 1.25 inches
• Manufactured from high-strength alloy for maximum tensile integrity
• Precision-rolled threads for superior strength and fatigue resistance

This ARP M12 x 1.75 threaded stud is engineered for high-performance applications where precise clamping force and fastener durability are critical. Designed with a 4.80-inch under-collar length, this stud provides a reliable mounting solution for heavy-duty components, offering superior strength and more consistent torque loading than standard hardware.

Using studs instead of bolts allows for more accurate assembly by eliminating the twisting force applied to the fastener during installation. This helps protect internal threads in aluminum or cast iron blocks and ensures a more uniform seal for critical engine or drivetrain assemblies.

• Brand: ARP
• Thread Size/Pitch: M12 x 1.75
• Under-Collar Length: 4.80 in
• Top Thread Length: 1.50 in
• Bottom Thread Length: 1.25 in

This ARP M12 x 1.750 threaded stud is engineered for high-strength applications where precision and reliability are critical. Designed to provide superior clamping force and fatigue resistance compared to standard hardware, it is an essential component for performance engine, drivetrain, or chassis assembly.

• Manufacturer: ARP
• Thread Diameter: M12
• Thread Pitch: 1.750
• Part Type: Metric Threaded Stud
• High-tensile strength construction for demanding load-bearing environments

This ARP 2000 single replacement stud is engineered to provide the high-strength clamping force required for demanding engine and drivetrain applications. Manufactured from proprietary ARP 2000 chromoly steel, this alloy is heat-treated to a typical tensile strength of 220,000 psi, offering superior fatigue resistance compared to standard Grade 8 or OE fasteners.

Ideal for custom builds or replacing a lost or damaged fastener from a complete kit, this stud features threads rolled after heat treatment to ensure maximum strength and thread engagement. The precision manufacturing process guarantees consistent preload during assembly, protecting your high-performance components under extreme loads.

• Brand: ARP
• Material: ARP 2000 Alloy
• Thread Pitch: M12 x 1.75
• Dimensions: 1.450 in / 4.600 in Length
• Fastener Style: Single Replacement Stud

This ARP broached stud is engineered for precision engine and drivetrain applications where high-strength clamping force and reliable fastener retention are critical. The broached design features an internal hex at the end of the stud, allowing for controlled installation and removal using an Allen wrench even when space is limited.

• Thread Specification: M11 x 7/16-20
• Broached end for simplified installation and height adjustment
• Precision-machined threads for consistent torque loading
• Engineered for high-performance automotive assembly and racing applications

This high-strength ARP stud provides a reliable fastening solution for specialized engine builds and performance assemblies requiring precise clamping force. The stud features a dual-thread configuration with an M11 x 1.5 base thread and a 7/16-20 top thread, engineered to withstand the stresses of high-performance environments.

The 6.300-inch overall length (OAL) is ideal for specific deck or housing depths, while the broached end design allows for easy installation and removal using a hex key, even in cramped engine bays where traditional wrench access is limited.

• Thread A: M11 x 1.5
• Thread B: 7/16-20
• Overall Length (OAL): 6.300 inches
• Design: Broached end for simplified installation
• Manufacturer: ARP (Automotive Racing Products)

This ARP2000 replacement stud is engineered for high-stress environments where extreme clamping force and fatigue resistance are mandatory. Manufactured from ARP's proprietary ARP2000 alloy, this fastener is designed to withstand the rigors of high-performance racing and forced induction applications, offering a significant upgrade over standard OE hardware.

The stud features precision-machined threads for consistent torque loading and is heat-treated to ensure maximum structural integrity. This specific fastener utilizes a dual-thread configuration with M11 x 1.5 metric threads on one end and 7/16-20 SAE fine threads on the other, making it an essential component for custom engine builds and specialty hardware replacement.

• Material: ARP2000 High-Strength Alloy
• Metric Thread Pitch: M11 x 1.5
• SAE Thread Pitch: 7/16-20
• Tensile Strength: Typically rated up to 220,000 psi
• Precision heat-treated and thread-rolled for maximum fatigue life

Designed for extreme cylinder pressures, this ARP L19 Series Head Stud Kit provides the ultimate clamping force for high-performance Nissan VQ35 engines. L19 is a premium, vacuum-melted steel alloy that is heat-treated to deliver a typical tensile strength of 260,000 psi—a significant upgrade over standard ARP2000 and 8740 chromoly materials.

These studs are a critical upgrade for high-boost forced induction or high-compression builds where head lift and gasket failure are common risks. Every stud is centerless ground to ensure perfect concentricity and thread-rolled after heat-treatment to achieve superior fatigue strength compared to lower-grade fasteners.

• Fits Nissan VQ35 series engines
• L19 material provides approximately 260,000 psi tensile strength
• Superior clamping force prevents head gasket failure in racing applications
• Precision-machined 12-point nuts and parallel-ground washers included
• Threads rolled after heat-treatment for maximum fatigue resistance
• Reference manufacturer part number: 202-4701 (L19 Material Upgrade)

This specialty fastener from ARP features a dual-thread design, transitioning from an M11x1.5 metric thread to a 7/16-20 standard SAE thread. Designed for precision applications where a metric-to-standard interface is required, this stud provides the consistent clamping force and reliability that professional engine builders demand.

As with all ARP hardware, this stud is engineered to withstand high-stress automotive environments. The threads are rolled to provide significantly higher fatigue strength compared to standard fasteners, ensuring long-term durability under load. This is a critical component for specialized mounting or conversion requirements in performance builds.

• Metric Side: M11 x 1.5
• Standard Side: 7/16-20
• High-strength construction for superior tensile integrity
• Precision-ground for accurate fitment
• Manufactured by ARP

This ARP high-strength specialty stud provides the superior clamping force and reliability required for demanding engine and chassis applications. Designed as a stepped fastener, it features an M11 x 1.5 thread on one end and a 7/16-20 thread on the other, making it an essential component for custom assemblies or specific thread conversion requirements.

Utilizing a stud instead of a traditional bolt allows for more consistent torque loading by placing the fastener in tension rather than shear. This design also protects the internal threads of your engine block or components from wear during repeated assembly and disassembly. ARP fasteners are engineered to exacting tolerances to ensure maximum fatigue life and resistance to stretching under high-stress conditions.

• Brand: ARP (Automotive Racing Products)
• Thread Size A: M11 x 1.5
• Thread Size B: 7/16-20
• Fastener Type: Stepped Stud
• Application: High-performance engine or chassis assembly

This ARP specialty fastener is engineered for high-performance applications requiring a transition between metric and SAE thread pitches. Featuring an M11 x 1.50 thread on one end and a 7/16-20 thread on the other, this stud provides a secure, precision-machined mounting solution for custom engine builds or specialized component installation where different hardware standards meet.

• Brand: ARP
• Thread A: M11 x 1.50
• Thread B: 7/16-20
• Configuration: Specialty Dual-Threaded Stud
• Quantity: Sold individually (one stud)
• Precision-rolled threads for maximum strength and fatigue resistance

This ARP specialty fastener is engineered to provide the high-tensile strength and precision required for demanding automotive applications. Featuring dual thread pitches, it utilizes an M11 x 1.50 metric thread on one end and a 7/16-20 SAE thread on the other, making it an essential component for custom engine assembly, specialty machining, or thread conversion projects.

• Thread A: M11 x 1.50 Metric
• Thread B: 7/16-20 SAE
• Brand: ARP (Automotive Racing Products)
• Designed for superior clamping force and durability
• Precision-ground threads for consistent torque loading

This ARP 1/2-inch diameter stud provides a precision fastening solution for custom engine builds and high-performance applications. Measuring 7.5 inches in overall length, this stud features a broached head, allowing for effortless installation and removal in tight clearances using a standard hex key.

• Diameter: 1/2 inch
• Overall Length: 7.5 inches
• Head Style: Broached for internal hex drive
• Application: Custom or replacement fastener
• Quantity: Sold individually (Single Stud)

ARP fasteners are manufactured to exacting tolerances to ensure consistent clamping force and thread engagement. This individual stud is ideal for replacing a damaged component or completing specialized hardware sets where standard kits do not meet specific length requirements.

This ARP 12-point nut is engineered for high-strength applications where precision and reliability are critical. Designed to exceed standard hardware specifications, this fastener provides the superior clamping force and durability required for demanding automotive engine, drivetrain, or chassis assemblies.

The 12-point head design offers a reduced wrenching diameter compared to traditional hex nuts, making it an ideal choice for tight clearances while providing increased surface contact for more accurate torque application. Like all ARP hardware, this nut is manufactured to exacting tolerances to ensure consistent performance under load.

• Brand: ARP
• Thread Size: M10 x 1.25
• Outer Diameter: 18mm
• Head Style: 12-Point
• Quantity: Single Nut

This ARP Custom Age 625+ fastener nut is engineered for high-load applications where extreme tensile strength and fatigue resistance are required. As part of ARP's premier fastener line, the Custom Age 625+ super-alloy provides significantly higher strength than standard ARP2000 or chrome moly, making it the ideal choice for critical engine, drivetrain, or chassis assemblies that undergo intense thermal and mechanical stress.

• Brand: ARP
• Series: Custom Age 625+
• Thread Size: M10 x 1.25
• Outer Diameter: M16
• Wrenching Style: 12-Point
• Quantity: Sold individually (One Nut)

The 12-point design allows for a higher torque application and better socket engagement in tight clearances, while the M16 O.D. ensures compatibility where space is at a premium. This precision-machined nut serves as a direct replacement for worn or damaged fasteners in high-performance racing and heavy-duty builds.

Maintain the integrity of your engine's assembly with this genuine ARP replacement nut, specifically designed for use with the ARP 204-4103 head stud kit. Whether you are refreshing your cylinder head or replacing a misplaced fastener during a build, this nut ensures the precise clamping force and thread engagement required for high-performance applications.

• Direct replacement nut for ARP head stud kit part number 204-4103
• Precision-machined threads for accurate torque loading and consistent preload
• Engineered to handle the extreme tensile loads and heat cycles of performance engines
• 12-point head design for maximum tool contact and clearance
• Sold individually; verify kit requirements before installation

This individual ARP replacement stud provides a precise solution for replacing a single damaged or lost fastener within an existing ARP hardware kit. Manufactured with the same metallurgy and heat-treating processes as their full sets, this stud ensures you maintain the uniform clamping force and high-tensile strength required for critical engine assemblies.

• Manufacturer: ARP
• Thread Size: M10
• Overall Length: 6.770 in
• Part Type: Replacement Stud
• Precision-ground and heat-treated for maximum reliability
• Ideal for engine builders needing a specific M10 fastener for custom or repair applications

This ARP replacement stud is engineered for critical applications where high-tensile strength and precision threading are mandatory. Whether you are replacing a component in an existing ARP kit or sourcing hardware for a custom engine or chassis project, this fastener provides the reliability and consistent clamping force that professional builders demand.

• Thread Diameter: M10
• Overall Length: 6.100 inches
• Precision-rolled threads for maximum fatigue life and strength
• Ideal for custom fabrication and specialized automotive assembly
• Manufactured by ARP for superior durability under high-stress conditions

This single ARP replacement stud is engineered for users who need to replace an individual component within the ARP 218-4702 fastener kit. Manufactured to the same exacting standards as the full kit, this stud ensures you maintain the uniform clamping force and high-tensile strength necessary for critical engine assemblies.

• Brand: ARP
• Part Type: Replacement Fastener
• Compatibility: Specifically for ARP Kit 218-4702
• Quantity: Single (1) Stud
• Material: High-strength chromoly steel
• Finish: Black oxide for corrosion resistance