Cast Iron GM LS1 6.0 Engine Block, 4.000" Bore 9.240" Deck Height, 6-Bolt Mains

Cast Iron GM LS1 6.0 Engine Block — 4.000" Bore, 9.240" Deck Height, 6-Bolt Mains

Elevate your GM LS1 6.0 build with Aeroflow Performance’s Cast Iron LS1 block. This heavy-duty, semi-finished bare block is engineered to be the rock-solid foundation for street-ported or race-inspired combinations, delivering exceptional strength and reliability where it matters most.

• Premium Class 32B cast iron construction: chosen for durability under high-performance stress.
• 4.000" bore and 9.240" deck height: designed to maintain a robust seal and work with off-the-shelf components.
• 6-bolt main caps with billet steel main caps: enhanced rigidity and hold-down under high power/torque scenarios.
• Dual knock sensor locations (valley and side): accommodates LS1 or LS2 style knock sensors.
• Rear cam position sensor compatibility: rear valley sensor option that can be blocked to run the front cam sensor only.
• Cam journal OD: STD 2.164" and standard cam location: straightforward assembly with common LS components.
• Very thick deck height: improves head gasket seal reliability and supports standard components such as camshaft, timing chain, oil pump/pan, and oil filter.
• Oil system compatibility: Oil filter STD; Oil pan STD; Timing cover STD; Timing chain/gears STD.
• Weight: 110 kg (242 lbs.)—solid mass and rigidity to reduce flex during high-RPM operation.
• Serial number location: Left Front & Main Caps for straightforward identification and traceability.
• Pickup available for local buyers: contact for shipping quote if needed.

Professional machining and assembly notes

• This block is designed as a semi-finished bare engine block that requires professional finish machining.
• Sizes referenced (deck height, bore, wall thickness, etc.) are nominal and within factory tolerances, with tighter tolerances possible when applicable.
• The block must be finished by a skilled machine shop to meet your specific component clearances.
• Cam bearing OD should be deburred before installation; when removing main caps, deburr the caps and block before re-installation to maintain correct main size.
• Cylinder bores will often require honing to achieve proper skirt clearance for oversized pistons; many aftermarket components are not drop-in without additional machining.
• Assembling with this block should be performed by an experienced engine builder to ensure reliable performance and proper tolerances across all systems.

Ideal starting point for high-performance LS builds, this block serves as a robust foundation for street-performance and track-savvy applications. A fresh, heavy-duty alternative to aging production blocks, it provides a solid platform ready for professional finish machining and precision assembly.