Best Engine Main Bolts & Studs of 2025

The Michigan LS Bolt Kit is an essential replacement for your LS engine's main cap fasteners. Designed to fit a wide range of LS-based V8 engines from 1997 to 2013, this kit includes everything you need: ten main cap bolts, ten main cap studs, and ten side cap bolts. This comprehensive set ensures a secure and reliable fit, enhancing the stability of your engine. By using quality stock replacements, you can trust that your engine will perform optimally, giving you peace of mind during operation. Upgrade your engine's components with this convenient and effective solution.

ARP Main Stud Kit is crafted from high-strength 8740 chrome moly steel, boasting a 200,000 PSI rating, much stronger than Grade 8 hardware. The rolled J-form threads are exceptionally durable, providing 1000% more strength than regular threads. Opting for main studs over bolts ensures precise torque readings and simplifies engine assembly, making your engine-building experience smoother and more accurate.

Speedmaster Main Stud Kit is designed for Small Block Chevy engines with 4-Bolt configuration. Constructed from high tensile strength chromoly steel, these studs can withstand up to 190,000 PSI. The kit includes 12-Point Nuts and Washers for easy installation. These premium-grade studs are heat-treated, ensuring strength and consistent torque readings. Perfect for engine builders seeking reliable and durable fastening solutions.

The ARP Stud Kit is a high-quality engine main stud and bolt kit that is proudly made in the USA. With compact package dimensions of 1.57 inches in height, 7.62 inches in length, and 4.44 inches in width, it is easy to store and handle. This kit is designed to provide superior strength and reliability for your engine, ensuring that all components stay securely in place during operation. By using this stud kit, you can enhance the performance and durability of your engine, giving you peace of mind while driving.

The Xotic Main Stud Kit is designed for Chevrolet Gen III/LS engines, ensuring a perfect fit for models from 1997 to the present. Its ultra-strong construction provides exceptional tensile strength, allowing you to handle high clamping forces far beyond standard head bolts. The easy installation process features broached ends and a detailed manual, making it user-friendly for both professionals and DIYers. Additionally, improved cap alignment helps reduce wear and enhances the durability of your engine block, ensuring reliable performance even under extreme conditions.

The IE Parts LS Bolt Kit is designed to enhance the performance of your GM LS engine. It includes ten inner main bolts, ensuring a secure fit by replacing the original OEM part number 12560272. Additionally, it comes with ten outer main bolts for the windage tray, which helps maintain optimal oil control. You will also find ten side bolts for the main cap, effectively replacing OEM part 12556127. This comprehensive set is compatible with a variety of Chevy and Pontiac models from 1997 to 2015, making it a convenient choice for your engine rebuild or upgrade.

ARP Main Bolt 1345202 is a high-performance main stud/bolt kit made in the USA. The package dimensions are 5.842 H x 22.098 L x 10.668 W (centimeters). This product falls under the category of Engine Main Bolts & Studs. The ARP Main Bolt 1345202 ensures durability and reliability for your engine, offering top-notch quality as it is made in the USA. The precise dimensions make it easy to install, providing a perfect fit for your engine.

The Speedmaster Stud Kit is designed for various GM LS engines, including LS1, LS2, LS6, LS7, and LSX models. Made from high-quality 8740 chromoly steel, these studs can withstand an impressive 190,000 PSI, ensuring durability and reliability in high-performance applications. Each kit includes precision-engineered 12-point nuts and washers, providing a secure fit and consistent torque readings. The heat-treated, parallel-ground washers enhance strength, making installation easier and more efficient for users. This stud kit is perfect for those looking to boost their engine's performance with dependable components.

The Xotic Main Stud Kit is a direct fit replacement for 5.9L 24V Dodge Cummins engines from 1998.5 to 2006. These studs are made from ultra-strong XOTIC 7200 material, providing superior tensile strength compared to standard options, ensuring your engine can handle high clamping forces. Installation is straightforward, thanks to broached stud ends and the included manual with diagrams. This kit also improves main cap alignment, reducing wear on block threads and preventing movement during clamping, thus enhancing the overall reliability of your engine under high pressure turbo systems.

The ARP Main Stud Kit is designed specifically for Honda H22A and H23A engines, ensuring a precise fit. Weighing only 2.7 pounds, this kit is lightweight yet robust, making installation easier for you. The vehicle-specific fit type means you can trust that these studs will perform well in your engine, providing essential support for critical components. With the quality and reputation of the ARP brand, you can have confidence in the durability and reliability of this main stud kit, enhancing your engine's performance and longevity.