Build the foundation of a high-performance GM LS-Series engine with the Edelbrock 54903U aluminum bare engine block. Designed for custom engine projects, this block features a natural aluminum finish and is supplied as a bare block, allowing builders to select the internal components, rotating assembly, valvetrain, and accessories that best match their application. Its LS-Series architecture provides a versatile starting point for street, race, and performance-oriented builds requiring a lightweight aluminum engine foundation.
The 54903U is configured with standard main bearing provisions, six-bolt main cap compatibility, and a one-piece rear main seal arrangement. It also uses a six-bolt cylinder head configuration and is intended for builders who understand LS engine assembly requirements and component compatibility. As a bare block, it does not include the complete internal or external components needed for a running engine. Proper machining, inspection, clearancing, and final assembly should be performed by a qualified engine builder using the selected crankshaft, pistons, connecting rods, bearings, seals, cylinder heads, and related hardware.
This Edelbrock LS-Series block is a practical choice for creating a tailored engine combination where strength, weight management, and flexible component selection are important considerations. The aluminum construction helps reduce engine weight compared with traditional cast-iron foundations, while the familiar GM LS-Series layout supports a broad range of performance components. Because this product is designated for air-restricted shipment and truck freight only, confirm delivery requirements and transportation arrangements before ordering. Use the Edelbrock brand and part number 54903U when verifying fitment, machining needs, and compatibility with the rest of your engine build.
Features:
- Brand and Part Number: Edelbrock 54903U LS-Series aluminum bare engine block
- Engine Family: Designed for GM LS-Series engine builds
- Construction: Lightweight aluminum block with a natural finish
- Main Configuration: Standard main bearing provisions with six-bolt main compatibility
- Rear Main Seal: One-piece rear main seal arrangement
- Cylinder Head Configuration: Six-bolt cylinder head design
- Bare Block Format: Supplied without the complete rotating assembly, valvetrain, accessories, or external engine components
- Shipping Requirement: Air-restricted and truck-freight-only product
