Original: $1,727.31
-70%$1,727.31
$518.19The Story
ARP Custom Age 625+ Head Stud Kit
For Chevy/GMC 6.6L Duramax Diesel (2001–2016)
When "standard" isn't enough, the Custom Age Head Stud Kit is the ultimate solution. While the popular 230-4201 kit is perfect for street and moderate tow builds, the Custom Age 625+ series is engineered specifically for high-boost, high-horsepower Duramax builds where cylinder pressures reach extreme levels.
This kit is the "big brother" to the standard 8740 and ARP2000 offerings, providing a massive jump in tensile strength to ensure your heads stay sealed under the most demanding racing or heavy-duty competition conditions.
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Key Features & Benefits
-
Custom Age 625+ Super-Alloy: A proprietary material that offers a typical tensile strength of 260,000–280,000 psi. This is significantly stronger than the 200,000–220,000 psi found in standard kits.
-
Maximum Clamping Force: Designed specifically for engines running high boost levels (often 40+ PSI) where head lift is a high risk.
-
Corrosion & Oxidation Resistance: The 625+ alloy demonstrates superior resistance to atmospheric corrosion and oxidation compared to standard chrome moly.
-
Precision Manufacturing: Like all ARP Pro Series fasteners, these are centerless ground for perfect concentricity and thread-rolled after heat treatment for maximum fatigue life.
-
Installation Ready: The ends of the studs are broached to allow for easy installation with an Allen wrench, which is a lifesaver when working in the tight engine bays of Silverado and Sierra trucks.
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Why Step Up to the 230-4202?
In the world of diesel performance, boost is king—but it comes at a price. If you are running a larger aftermarket turbo, compound setups, or high-flow injectors, the cylinder pressure can literally stretch standard head fasteners, allowing the head to "hover" and blow the gasket.
The Custom Age 625+ material provides the extra insurance you need. It offers nearly 30% more tensile strength than standard ARP2000 studs, making it the highest level of protection available for the Duramax platform.
Note: This kit includes the complete set of studs, 12-point nuts, parallel-ground washers, and a packet of ARP Ultra-Torque lubricant.
Description
ARP Custom Age 625+ Head Stud Kit
For Chevy/GMC 6.6L Duramax Diesel (2001–2016)
When "standard" isn't enough, the Custom Age Head Stud Kit is the ultimate solution. While the popular 230-4201 kit is perfect for street and moderate tow builds, the Custom Age 625+ series is engineered specifically for high-boost, high-horsepower Duramax builds where cylinder pressures reach extreme levels.
This kit is the "big brother" to the standard 8740 and ARP2000 offerings, providing a massive jump in tensile strength to ensure your heads stay sealed under the most demanding racing or heavy-duty competition conditions.
Â
Key Features & Benefits
-
Custom Age 625+ Super-Alloy: A proprietary material that offers a typical tensile strength of 260,000–280,000 psi. This is significantly stronger than the 200,000–220,000 psi found in standard kits.
-
Maximum Clamping Force: Designed specifically for engines running high boost levels (often 40+ PSI) where head lift is a high risk.
-
Corrosion & Oxidation Resistance: The 625+ alloy demonstrates superior resistance to atmospheric corrosion and oxidation compared to standard chrome moly.
-
Precision Manufacturing: Like all ARP Pro Series fasteners, these are centerless ground for perfect concentricity and thread-rolled after heat treatment for maximum fatigue life.
-
Installation Ready: The ends of the studs are broached to allow for easy installation with an Allen wrench, which is a lifesaver when working in the tight engine bays of Silverado and Sierra trucks.
Â
Why Step Up to the 230-4202?
In the world of diesel performance, boost is king—but it comes at a price. If you are running a larger aftermarket turbo, compound setups, or high-flow injectors, the cylinder pressure can literally stretch standard head fasteners, allowing the head to "hover" and blow the gasket.
The Custom Age 625+ material provides the extra insurance you need. It offers nearly 30% more tensile strength than standard ARP2000 studs, making it the highest level of protection available for the Duramax platform.
Note: This kit includes the complete set of studs, 12-point nuts, parallel-ground washers, and a packet of ARP Ultra-Torque lubricant.
