Bolts

Bolts: the fasteners that hold clamp load where the engine needs it most

Engine bolts do one job that matters more than it looks: they hold a specific clamp load across a joint and keep holding it through heat cycles, vibration and cylinder pressure. A head bolt or cylinder stud clamps the head to the block so the gasket seals combustion. An up-pipe bolt keeps an exhaust joint tight where heat and rattle try to loosen everything. Undersized or tired fasteners let joints move, gaskets weep and threads pull. Fitting the right bolt, torqued right, is what makes the rest of the build stay together.

What ThreePiece stocks

There are 23 products in this category right now, spread across four brands: ARP (16 of the sample), Vibrant (4), Wehrli (2) and S&S Cycle (1). Prices run from $31 to $270, the current range for what is in stock rather than a fixed promise. At the top sits the S&S Cycle 2017 M8 cylinder stud and head bolt kit. The Wehrli side covers diesel exhaust joints with the 17-24 L5P Duramax up-pipe bolt kit and the 01-16 LB7/LLY/LBZ/LMM/LML Duramax up-pipe bolt kit. For general fastening work, ARP offers stainless hex and 12-point bolts like the 1/2-13 x 2.750 hex SS 5-pack and the M10 x 1.25 x 60mm 12-point SS 5-pack, while the Vibrant 3/4-16 replacement oil filter bolt covers a common repair thread.

How to choose

Start with the job. If you are replacing a factory joint on a known engine, a vehicle-specific kit like the Wehrli Duramax up-pipe kits or the S&S M8 stud and head bolt kit takes the guessing out of length, thread and count. If you are building or fabricating and need loose fasteners in a known size, the ARP hex and 12-point packs let you buy the exact thread pitch and length you need in five-packs. The 12-point head clears tight spaces a hex head cannot; the hex is easier to reach with a standard socket. The Vibrant filter bolt is a single-thread replacement part, not a kit. Match thread size, length and required clamp load to your application before ordering.

What else you need with it

Bolts rarely go in alone. If you are opening a joint, plan to renew the seal at the same time from Head Gaskets or a full Gasket Kits. Building deeper means Pistons and Bearings. For plumbing and mounting jobs, see Fittings and Adapters. Browse everything in the parent Engine Components section for the rest.

Fitment and ordering

Fitment data is listed for 3 of these products, with sample coverage on Chevrolet Silverado, Harley-Davidson M8 and GMC Sierra across roughly 2001-2024. The rest are sized fasteners you match by thread and length. If you are unsure a kit fits your engine, call fitment help at 813-535-5801 or reach us through contact us before buying. Orders ship with free shipping, and Affirm and Katapult financing is available.

Bolts: the fasteners that hold clamp load where the engine needs it most

Engine bolts do one job that matters more than it looks: they hold a specific clamp load across a joint and keep holding it through heat cycles, vibration and cylinder pressure. A head bolt or cylinder stud clamps the head to the block so the gasket seals combustion. An up-pipe bolt keeps an exhaust joint tight where heat and rattle try to loosen everything. Undersized or tired fasteners let joints move, gaskets weep and threads pull. Fitting the right bolt, torqued right, is what makes the rest of the build stay together.

What ThreePiece stocks

There are 23 products in this category right now, spread across four brands: ARP (16 of the sample), Vibrant (4), Wehrli (2) and S&S Cycle (1). Prices run from $31 to $270, the current range for what is in stock rather than a fixed promise. At the top sits the S&S Cycle 2017 M8 cylinder stud and head bolt kit. The Wehrli side covers diesel exhaust joints with the 17-24 L5P Duramax up-pipe bolt kit and the 01-16 LB7/LLY/LBZ/LMM/LML Duramax up-pipe bolt kit. For general fastening work, ARP offers stainless hex and 12-point bolts like the 1/2-13 x 2.750 hex SS 5-pack and the M10 x 1.25 x 60mm 12-point SS 5-pack, while the Vibrant 3/4-16 replacement oil filter bolt covers a common repair thread.

How to choose

Start with the job. If you are replacing a factory joint on a known engine, a vehicle-specific kit like the Wehrli Duramax up-pipe kits or the S&S M8 stud and head bolt kit takes the guessing out of length, thread and count. If you are building or fabricating and need loose fasteners in a known size, the ARP hex and 12-point packs let you buy the exact thread pitch and length you need in five-packs. The 12-point head clears tight spaces a hex head cannot; the hex is easier to reach with a standard socket. The Vibrant filter bolt is a single-thread replacement part, not a kit. Match thread size, length and required clamp load to your application before ordering.

What else you need with it

Bolts rarely go in alone. If you are opening a joint, plan to renew the seal at the same time from Head Gaskets or a full Gasket Kits. Building deeper means Pistons and Bearings. For plumbing and mounting jobs, see Fittings and Adapters. Browse everything in the parent Engine Components section for the rest.

Fitment and ordering

Fitment data is listed for 3 of these products, with sample coverage on Chevrolet Silverado, Harley-Davidson M8 and GMC Sierra across roughly 2001-2024. The rest are sized fasteners you match by thread and length. If you are unsure a kit fits your engine, call fitment help at 813-535-5801 or reach us through contact us before buying. Orders ship with free shipping, and Affirm and Katapult financing is available.