Jack Bolt Sleeve 1-1/8in-12

The Jack Bolt Sleeve 1-1/8in-12 from Allstar Performance is a precision threading component designed for engine builders, fabricators, and automotive enthusiasts who require reliable fastening solutions in high-stress applications. This threaded sleeve serves as a critical insert or reinforcement element in cylinder heads and engine blocks where standard bolt holes need additional support or size correction.

Engineered to exacting standards, this sleeve features a 1-1/8 inch outer diameter with a 12 threads-per-inch pitch, ensuring compatibility with specific applications in engine work. The precise threading geometry guarantees full contact with both the bore and the fastener, distributing load evenly and preventing thread stripping under dynamic engine conditions, particularly in aluminum heads or previously damaged mounting points.

The Jack Bolt Sleeve 1-1/8in-12 is ideal for those restoring classic engines or building competition powerplants, providing the necessary thread pitch and diameter to restore fastening integrity without compromising structural strength. Its 7-inch length allows for easy installation in tight engine compartments while maintaining the rigidity required for reliable clamping force and vibration resistance.