Engines and Components› Engines, Blocks and Components

LS1

LS1 5.7L V8 Aluminum Bare Engine Block

$999.99

SKU: 12559378

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

The Chevrolet LS1 is a 5.7L bare engine block with casting number 12559378. This aluminum block is a component for V8 engines and features 6-bolt main caps. It is a used OEM part, and buyers should check pictures for condition.
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The Chevrolet LS1 bare engine block, with casting number 12559378, is an original equipment manufacturer (OEM) component designed for 5.7L V8 applications. This aluminum block is a foundational piece for engine builds and features 6-bolt main caps for enhanced strength. The block is described as used, and potential buyers are advised to carefully review the provided images to assess its specific condition. This specific engine block is identified with the LS1 designation and is often associated with vehicles such as the 1997-2004 Chevrolet Corvette, 1998-2002 Chevrolet Camaro (Z28/SS), 1998-2002 Pontiac Firebird/Trans Am, and the 2004 Pontiac GTO. It is a 346 cubic inch (5.7L) engine block, commonly found in performance-oriented General Motors vehicles. The product listing indicates it is a "used OEM" part, emphasizing the need for buyers to examine its condition closely through the available pictures.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandLS1
Part Number12559378
CategoryEngines and Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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