Engines and Components› Cylinder Heads and Components

Chevrolet

Gen III V8 LS Engine Cylinder Head

$363.74

SKU: 12564243

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Overview

The GM 12564243 Cylinder Head is an aluminum alloy V8 engine component designed for Generation III applications. It features a cathedral intake port design for enhanced combustion efficiency and is noted for its durability and precise engineering. This head is commonly used in trucks, vans, SUVs, and performance vehicles.
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This third-generation GM head is a direct replacement or upgrade for various Generation III and IV V8 LS series engines, including those found in applications like the LS6, LS1, LQ4, and LQ9. Originally featured on LS6 engines from 2001 to 2006, these heads were initially developed for the C5 Corvette and later adapted for truck applications. They offer enhanced performance through improved airflow characteristics compared to earlier models like the 241 heads. The 243 heads come equipped with 1.7 ratio rocker arms, which enable greater valve lift than the 1.8 ratio rockers found on some other LS heads, leading to increased airflow and power potential. Key features of the 243 cylinder heads include their aluminum construction, a 65cc combustion chamber for a higher compression ratio, and a valve system that can support higher lifts. They are also noted for their compatibility with higher-lift camshafts and improvements in the valve train, contributing to overall engine efficiency and horsepower gains. These heads are suitable for both performance builds and everyday driving conditions, offering durability and precise engineering.

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

BrandChevrolet
Part Number12564243
CategoryEngines and Components
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