L-head engine

engineering

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Last updated

June 30, 2026

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An L-head engine is a type of internal-combustion engine where the intake and exhaust valves are located in compartments on the same side of the cylinder head, within the engine block itself. This design contrasts with valve-in-head engines, where both valves are situated directly in the cylinder head. In an L-head configuration, the cylinder block is extended to house these valves and their associated passages. The cylinder head then primarily serves as a cover, providing space for spark plugs and forming the combustion chamber above the cylinder bore.123

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gasoline engine
Cylinder block
…which has largely replaced the L-head type, has its valves entirely in the cylinder head. The cylinder block of the L-head engine is extended to one side of the cylinder bores, with the valve seats and passages for inlet and exhaust, together with the valve guides, formed in this extension…
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…which has largely replaced the L-head type, has its valves entirely in the cylinder head. The cylinder block of the L-head engine is extended to one side of the cylinder bores, with the valve seats and passages for inlet and exhaust, together with the valve guides, formed in this extension…
Read More