What Is a Long Block Engine? (And What's Included)

When shopping for a replacement engine you will see terms like long block, short block, and crate engine. Knowing what each includes helps you plan your swap, budget correctly, and avoid ordering the wrong thing.

What a long block includes

A long block is a complete engine assembly. It includes the engine block, crankshaft, pistons, connecting rods, and the cylinder head(s) with the valvetrain installed. In other words, the entire core of the engine is assembled and ready to accept your accessories.

Long block vs short block

A short block includes the block, crankshaft, pistons and rods — but not the cylinder heads. A long block adds the heads and valvetrain. Most buyers want a long block because it is far closer to a complete, drop-in engine.

Long block vs crate engine

A crate engine is typically a complete, ready-to-run engine that may include accessories and sometimes even the intake and ignition. It costs more. A long block is the smart middle ground: the expensive core is done, and you reuse your own good accessories.

What is usually NOT included

Bolt-on accessories are typically not included with a long block: the alternator, AC compressor, starter, power steering pump, intake manifold in some cases, and the wiring harness. The good news is that these parts on your old engine are usually fine, so you keep them for the swap.

How to plan your swap

Before installing a used long block, plan to replace wear items: gaskets and seals, the water pump and thermostat, and timing components if they are at service interval. Prime the oil system before first start. This protects both the engine and your warranty.

Frequently asked questions

Does a long block come with heads?

Yes. A long block includes the cylinder head(s) with the valvetrain already installed, along with the block and rotating assembly.

What is the difference between a long block and a complete engine?

A complete (or crate) engine adds bolt-on accessories like the alternator, starter, and intake. A long block is the assembled core only — you transfer your accessories onto it.

Do I need to transfer parts to a long block?

Yes. You move your accessories — alternator, AC compressor, starter, sensors, intake and wiring — from your old engine onto the long block, replacing any worn ones.

Is a used long block a good deal?

Usually, yes. The most expensive, hardest-to-build parts come assembled, while you reuse accessories you already own — often the best value for a reliable repair.

The bottom line

A long block gives you the complete engine core, ready for your accessories, at a much better price than a full crate engine. Not sure what your vehicle needs? Call 999-999-9999 with your VIN and we will confirm exactly what comes with your engine.