5.3-5.7L Iron LS Engine Block

Boostline Performance proudly introduces our premium line of machined 5.3L GM engine blocks - precision-engineered for serious performance builders who demand reliability under extreme conditions.

Perfect for the customer who wants to build their own engine and needs a good foundation to start with.

Each block starts with a seasoned GM Gen 3 or 4 Iron 5.3L foundation, then undergoes our proprietary machining process on state-of-the-art Rottler CNC equipment.  These blocks get fully machined (Zero Decked, Bored to your specification and Torque Plate Honed at our facility using seasoned GM engine blocks on our Rottler CNC machines. 

Whether you're building a street monster or an all-out competition engine, our flexible options accommodate bore sizes from 3.800-3.903", giving you maximum flexibility for your specific displacement goals.

Features:

• Allows 900+ HP Builds (excellent for turbo builds)
• All Blocks Are Seasoned and Inspected GM Cores
• OEM GM Main Caps
• Bore Sizes Available from 3.800-3.903”
• Bored To Your Specified Bore Size And Torque Plate Honed
• Zero Decked
• Comes With New Cam Bearings Installed
• DOD/AFM Holes are tapped and plugged on all Gen 4 blocks