Alloyboltz Stainless Hex Bolt Kit 3/8 Inch

Description

Product Overview

The Alloyboltz Stainless Hex Bolt Kit is engineered for serious big‑block enthusiasts who demand precision, durability and corrosion resistance. Each of the 254 bolts is forged from 304 stainless steel, delivering a Grade 10.9 tensile strength that meets or exceeds OEM specifications. The bolts feature a 3/8‑16 UNC thread profile, right‑hand thread style, and a Class 3A thread class for a tight, leak‑free fit. A machined exterior finish not only adds a professional appearance but also enhances resistance to wear and environmental exposure. The hex head design (hexagon bolt) allows for easy installation with standard 1/2‑inch wrenches or impact drivers, reducing installation time on the shop floor.

Key specifications include a 0.38‑inch diameter, premium manufacturer grade, and a full range of component parts covering intake manifolds, valley covers, timing covers, water pumps, oil pans, thermostat housings, distributors, coil brackets, fuel pumps, valve covers, headers, crank and fan pulleys, as well as a dedicated carburetor stud kit compatible with Carter, Edelbrock and Holley carbs. The kit is packaged in individually labeled sub‑kits, making inventory management and part identification straightforward for both professional mechanics and dedicated DIYers.

Usage

This bolt kit is designed for a wide variety of big‑block engines, including 383, 400, 413, 426 Wedge and 440 non‑EFI applications. Whether you are rebuilding a classic muscle car, performing a high‑performance upgrade, or simply replacing worn fasteners, the kit provides the exact hardware needed for critical engine components. The stainless steel construction ensures the bolts will not seize or corrode in high‑temperature zones such as the exhaust header area, water pump housing, or valve cover. The included small‑OD header washers are specifically engineered to clear large‑tube headers, preventing warping and ensuring a secure seal.

Mechanics will appreciate the pre‑sorted, individually packaged sets that streamline the assembly process. The hex head design works seamlessly with torque wrenches, allowing precise tightening to the manufacturer‑specified torque values, which is essential for maintaining engine compression and preventing leaks. This kit is also suitable for aftermarket component installations, offering a reliable fastening solution for performance upgrades.

Why Choose Us

Alloyboltz stands out in the automotive fastener market by combining premium material selection with rigorous quality control. Each bolt undergoes a hardness test to confirm Grade 10.9 compliance, and the stainless steel is sourced from certified 304 alloy suppliers, guaranteeing consistent corrosion resistance even in harsh engine environments. Our manufacturing process includes a precision machining step that produces a uniform exterior finish, reducing the risk of stress concentrations that can lead to bolt failure.

We back our products with a no‑discontinue policy, ensuring that you will always have access to replacement parts that match the original specifications. Customer reviews average 4.1 out of 5 stars, reflecting satisfaction with fit, durability and the comprehensive nature of the kit. Additionally, the kit’s best‑seller rank in the Automotive Replacement Engine Main Bolts & Studs category demonstrates its popularity among professionals and enthusiasts alike.

Key Features

• 304 stainless steel construction provides superior corrosion resistance and long‑term durability.
• Grade 10.9 tensile strength meets OEM performance standards for high‑stress engine applications.
• Complete 254‑piece kit covers all major big‑block engine mounting points, reducing the need for multiple purchases.
• Machined exterior finish and hex head design enable easy installation and precise torque application.
• Includes specialized small‑OD header washers and carburetor studs compatible with major carb brands.

FAQ

What engines are compatible with this bolt kit?

The kit is compatible with 383, 400, 413, 426 Wedge and 440 non‑EFI big‑block engines. It covers all major mounting points for these engine families.

Are the bolts suitable for high‑temperature applications?

Yes. The 304 stainless steel material retains strength at elevated temperatures and the Grade 10.9 rating ensures the bolts can handle the stresses found in exhaust and header installations.

Can I use these bolts for aftermarket performance parts?

Absolutely. The kit includes a variety of fasteners and washers designed to work with common aftermarket components such as large‑tube headers, high‑flow intake manifolds and performance carburetors.

How do I ensure proper torque on these bolts?

All bolts are sized for standard torque specifications. Refer to your engine’s service manual for the exact torque values and use a calibrated torque wrench to achieve the correct preload.

Is there a warranty on the Alloyboltz bolt kit?

Alloyboltz offers a limited warranty against material defects for the life of the product. If a bolt fails due to a manufacturing issue, we will replace it at no cost.