ARP Pro Series flexplate bolt kit for Gen II/LS small block Chevrolet — M11 x1.5 bolts, 12‑point heads

These ARP 244-2901 bolts are purpose-built to secure the flexplate to the crankshaft on Gen II/LS-series small block Chevrolet engines. Forged from aerospace-grade alloy, heat-treated, and precision-machined, they replace weaker factory hardware with a thicker shank diameter, improved register, and a flat 12-point head that resists rounding during installation. The kit uses M11 x 1.5 threads and is tightened with a 3/4-inch wrench, making it a direct, high-performance upgrade for builders and technicians who demand reliability under higher loads.

Why choose ARP Pro Series bolts over stock flexplate hardware?

ARP's Pro Series bolts are manufactured to higher material and process standards than typical OE parts. The aerospace alloy and controlled heat-treatment deliver a marked increase in tensile strength and fatigue resistance, reducing the chance of bolt stretch or failure during heavy-duty use.

• Forged aerospace-grade alloy for improved strength
• Heat-treated prior to thread-rolling to maintain integrity
• Larger shank diameter for better load distribution
• Flat 12-point head for secure wrench engagement and less rounding

How do these bolts improve installation and serviceability?

The ARP 12-point head design presents a full, flat contact surface for a 3/4-inch tool, minimizing slippage and damage when torquing. Precision machining and consistent threads help ensure repeatable clamping force and easier torque verification during assembly or maintenance.

• M11 x 1.5 thread pitch matches LS crank specifications
• 3/4-inch wrenching for common shop tools
• Precision threads reduce cross-thread risk
• Consistent factory-like fit with improved register

Will these bolts fit my Gen II/LS small block Chevy crankshaft?

Yes—this ARP 244-2901 kit is specified for Gen II/LS-series small block Chevrolet applications that use M11 x 1.5 flexplate fasteners. Confirm your engine uses the same thread size and bolt pattern before installing; when matched, these bolts provide a direct, high-reliability replacement.

• Designed for Gen II/LS small block Chevy crank interfaces
• Thread size: M11 x 1.5—verify against your crank or service manual
• Direct-replacement form factor for common LS flexplates
• Ideal when upgrading from factory hardware or during rebuilds

What performance and longevity benefits can I expect?

Upgrading to ARP Pro Series fasteners reduces the risk of bolt failure under high torque and cyclic loading, which is especially important for modified engines or heavy-duty use. Stronger bolts maintain clamp load and alignment longer, contributing to fewer service interruptions and safer drivetrain operation.

• Higher tensile strength reduces stretch and loosening
• Better fatigue resistance under repeated torque cycles
• Improved register reduces misalignment risk between flexplate and crank
• Durable finish and machining for long-term reliability

Who is this for? The ARP 2442901 Pro Series flexplate bolt kit is aimed at enthusiasts, performance builders, and professional mechanics working on Gen II/LS small block Chevrolet engines who want a robust, long-lasting upgrade to factory hardware. It’s suited for engine builds with increased power, repeated track or towing use, or any overhaul where dependable fasteners reduce the chance of drivetrain issues. Always verify thread size and torque specifications during installation and follow ARP’s assembly recommendations for optimal results.