What is the difference between a long block and a short block Subaru?
In Subaru engine terminology, a long block is a more complete engine core than a short block. A short block typically includes the block, crankshaft, pistons, and connecting rods, while a long block adds the cylinder heads and valvetrain. Exact inclusions vary by model and by seller, so it’s essential to check the vendor’s specification.
Short block basics in Subaru engines
The short block represents the engine’s lower assembly—the core components needed to turn fuel into motion—without the cylinder heads or top-end hardware. The list below covers what is usually bundled with a short block, with caveats about vendor variation.
- Engine block
- Crankshaft
- Connecting rods
- Pistons
Note: Some suppliers may include other parts such as the oil pump or flywheel, but these are not universally included. Always verify the parts list before purchase.
Long block basics in Subaru engines
A long block adds the cylinder heads and valvetrain to the core block, bringing more of the engine’s top-end assembly into one package. The list below reflects common inclusions, though variations exist by model and supplier.
- Cylinder heads
- Valvetrain components (camshafts, lifters, valves, and related hardware)
- Timing components (timing belts/chains, tensioners, guides)
- Often the timing cover and front cam timing gearset
- May include certain gaskets or seals, depending on vendor
As with short blocks, contents can vary. Some vendors may exclude intake/exhaust manifolds, turbochargers, and ancillaries.
Key differences and practical implications
Markets, model years, and dealer networks mean that “long block” and “short block” are not strictly standardized terms. The following points capture how the distinction matters in practice for Subaru owners.
- Scope of parts: Long blocks cover heads and valvetrain; short blocks do not.
- Labor and cost: A long block generally costs more and takes longer to install.
- Compatibility: A long block is closer to a complete engine; a short block may require additional components to run.
- Remanufacturing options: Reman blocks vary by supplier; verify warranty terms.
- Model variation: Subaru EJ, FA, and FB engine families have different head designs; ensure compatibility with your model.
- Vendor verification: Always request a detailed parts list and photos to confirm inclusions.
In all cases, you should confirm exactly what’s included before purchasing and whether any ancillary parts must be sourced separately.
Buying tips for Subaru engines
To avoid surprises, use the following questions when shopping for a long block or short block for a Subaru. This helps ensure you get the right package for your repair or rebuild.
Questions to ask vendors
- Which parts are included in this block (heads, camshafts, timing components, gaskets, etc.)?
- Are intake/exhaust manifolds, turbochargers, or ancillaries included?
- Is a new or refurbished crankshaft, pistons, and rods used, and what are the tolerances?
- What is the warranty, and what conditions apply?
- Are timing belts/chains and water pump included or required to be purchased separately?
Knowing the exact inclusions helps you budget accurately and avoid duplication of parts during installation.
Summary
For Subaru engines, the key difference between a long block and a short block is the scope of included components: long blocks add cylinder heads and valvetrain to the block core, while short blocks provide the block, crank, pistons, and rods. Always verify the vendor’s exact inclusions, model compatibility, and warranty terms before purchase to ensure a smooth rebuild or replacement.
