Engines and Components› Cylinder Heads and Components

ARP CA625+

CA625+ Head Stud Kit

$1,530.00

SKU: AR9994209-CA

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

The ARP CA625+ is an engine fastener kit designed for Nissan RB DOHC and Twin Cam engines. These head stud kits feature Custom Age 625+ material, known for its strength and reliability. The studs are 1/2" in diameter, centerless ground, and heat-treated prior to thread rolling.
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The ARP CA625+ head stud kit is engineered for Nissan RB DOHC and Twin Cam engines, including models such as the RB20DET, RB25DET, RB26DETT, RB30ET, and CA18DET. These studs are constructed from ARP's proprietary Custom Age 625+ material, offering superior tensile strength and fatigue life compared to standard aerospace alloys. The studs feature a 1/2" diameter and are centerless ground for precise concentricity. They undergo heat treatment before thread rolling to ensure maximum thread strength and durability. The kit also includes 12-point nuts, designed for high clamping force and ease of use with appropriate tools. This kit is a direct replacement for factory head bolts, providing a more secure and reliable clamping solution for high-performance engine applications. The Custom Age 625+ material offers excellent resistance to fatigue and stretching, crucial for maintaining head gasket seal integrity under demanding conditions.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandARP CA625+
Part NumberAR9994209-CA
CategoryEngines and Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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