What’s the difference between long and short block?

Both engine types are identical in size while having different names. The only thing that separates them is what they carry. The engine block, crank, and pistons are the usual components of a short-block engine package. The term “short block” refers to an engine having a smaller number of parts and typically a shorter warranty.

All of the components of a short block engine are included in a long block engine along with a cylinder head, camshaft, and valve-train. The majority of replacement and aftermarket engines can be ordered with short or long blocks. The sort of engine to choose for a certain car — and for a specific budget — depends on a number of additional considerations.

Long and short blocks

A fully completed engine that is supplied in a crate from the manufacturer to the installer is known as a turn-key or crate engine. The installer only needs to install it in a car, turn the key, and drive away. A turn-key engine kit typically contains a throttle pedal, spark plugs, airflow sensors, and other miscellaneous elements in addition to the components that come with a long block.

Well, in this article, we’ll be looking at long blocks vs. short blocks. That said, we’ll go over the answers to the following questions:

  • What are long and short blocks?
  • Which warranty is longer and better?
  • What are the differences between the two?
  • How much does long and short block cost?
  • Which is better, the long or short block?

Ok, let’s dive in!


What are long and short blocks?

Long Block Engine

In some ways, a long block engine is a finished version of a short block. It includes a camshaft, lifters, valve train, and cylinder head in addition to the assembled block. An oil pan, water pump, and valve covers could also be included with a long block. When diagnostics show that a vehicle needs an engine overhaul, long blocks are typically used.

Even though a long-block engine has more parts than a small block, it still lacks all of the necessary components. Among other things, the fuel system, intake manifold, exhaust manifolds, and electrical components are not included in a long block. Consider obtaining a “turn-key” engine if you need to replace these parts or every other piece of the engine assembly.

Some individuals use the terms short block and long block interchangeably or as synonyms for small block and big block engines. Starting with the classification of small block or big block engines as a description of engine size, there are substantial variances between these terms. The term “short block” or “long block” describes how many assembly components are present.

Short Block Engine

A short block engine is the engine’s bottom end. Along with the cylinder block, it also contains a few other crucial engine components such as the crankshaft, cam pistons, and connecting rods. The rotating assembly is another name for these components.

Some short blocks might have camshafts and timing belts because engine manufacturer companies frequently make minor changes to their kits. All short-block engines need extra components such as oil pumps, cylinder heads, and gaskets that must be bought individually.

Short block engines are perfect for people who want to learn how to build an engine independently. Building a short-block engine offers a more complex and practical solution to engine replacement and is a terrific learning experience.

Which warranty is longer and better?

Long-block engines typically come with longer and more thorough warranties than short-block ones. The extra pieces put on a short block are not covered by warranties because they only apply to the items included in the initial purchase. Consider getting a professional mechanic to install the engine because faults brought on by defective fittings are not covered by warranties for either type of engine.

Depending on the business you buy from, any extra parts you need for a short block can be purchased with a separate warranty. To ensure the quality of the work, a mechanic could provide an installation warranty if you purchase a short-block engine.

What are the differences between the two?

The following are the major differences between the long and short blocks:

  • The block, crank, rods, and pistons are all parts of a short block when it is fully constructed.
  • Other components, such as the camshaft, timing chain, and covers, may be present in short blocks.
  • The heads and usually the valvetrain is added to short blocks to make long blocks.
  • The oil pan, carburetor (or throttle body), distributor (or coil packs), and covers for the timing chain, valves, and an oil pan are also included with deluxe long blocks.
  • The term “bare blocks” refers to bare iron or aluminum blocks that may require machine work before being assembled into an engine.

This video will help you understand the difference between long and short blocks better:

How much does long and short block cost?

Typically, a short-block engine is less expensive than a long-block engine. Long-block engines cost between $1,500 and $5,000 as of 2021, whereas short-block engines cost between $1,000 and $3,000. The make, model, and year of the car the engine is built for also affect the price difference.

However, a short-block engine necessitates the purchase of extra parts that come with the long block as standard. A short block also takes longer to install because so many elements need to be installed. The large block typically turns out to be a better deal when labor costs and additional components are taken into account.

Which is better, the long or short block?

A long-block engine often performs better and more consistently than a short-block engine. Long blocks are less prone to malfunction as a result of fitting process mistakes because more pieces are preloaded on them. Long blocks also have components that wear out more evenly and require fewer replacements.

Not all long blocks will function well with the brand and model of your vehicle, just like other sub-assembled auto parts. Make sure the long block you are installing is compatible with your car’s electronic control unit and transmission system if you want it to run as well as the standard engine.

A small block engine, on the other hand, gives you more options for the variety of external parts you can add. If you spend money on high-quality parts and accessories, you can anticipate that a short block will operate better than a long block. Think about the cylinder head assembly, which has a direct impact on the engine’s output horsepower.

A small block does not come with a cylinder head already attached, in contrast to a long block. You are free to select any head that best suits the performance you desire. The power output of a stock engine can be surpassed by a fantastic head on a great short block.

If significant internal components of the original engine are beyond repair but other external components are still usable, take into account choosing a short block over a remanufactured engine. Consider getting a long block for your engine swap instead if these parts are broken and the combined cost of buying the short block and other components is close to the cost of buying a long block.

Here are the pros and cons of both blocks:

Short Block Pros

  • Less expensive upfront than a long block.
  • Greater customizing potential.
  • The benefit of learning by doing things yourself.

Short Block Cons

  • Additional assembly is required.
  • Longer installation period.
  • More challenging.
  • You need to purchase additional, potentially more expensive parts.
  • You must adjust those components for your block.
  • There is only a block warranty.

Long Block Pros:

  • Already tuned pieces are included.
  • More components are covered by the warranty.
  • Plug-and-play is getting closer.

Long Block Cons:

  • Greater upfront costs compared to a small block.
  • Reduces the enjoyment that comes from building an engine.
  • It isn’t fully assembled like a turnkey engine.

Related Article


What is a better short block or long block?

A long-block engine often performs better and more consistently than a short-block engine. Long blocks are less prone to malfunction as a result of fitting process mistakes because more pieces are preloaded on them.

What does a short-block engine do?

Engines with short blocks are not operational. They are made up of a crankshaft, connecting rods, and an engine block. But a short block is devoid of the fuel system, cylinder head, liners, gaskets, rings, timed gearing, and other ancillary components.

What makes an engine a long block?

Because of its longer list of parts, long block engines receive their moniker. Like the short block, they have an engine block, crank, and pistons, but they also have a cylinder head, a camshaft, and a valve train. In some situations, your order will also include a valve cover and an oil pan.

Does the long block include a turbocharger?

Turbochargers, starters, alternators, air conditioning compressors, fuel injectors, and spark plugs are not included with LF long blocks. The same GM part number is used for LF4 large blocks in both A8 and M6 applications. Each type of gearbox has a different set of oil pans, though.

What does a short block need to run?

A short block has a crank, pistons, and connecting rods but is otherwise incomplete. Additional components, such as cylinder heads, gaskets, an oil pump, etc., are needed. You have the option to customize the short block because it isn’t finished.

Does a long block come with injectors?

Yes, they do come with injectors.


Finding the ideal match for your car can be made easier by understanding the differences between a short-block and a long-block engine package. Get price quotations for both short and long-block engines from various vendors before making a purchase.

The details of each engine type, together with an anticipated installation cost, should be included in the estimates you receive. In order to prevent future unnecessary replacements, it would be preferable to always have a thorough diagnostic examination performed on the defective engine.

Recognize the primary cause of your engine failure, then have a qualified mechanic address the issue when the engine is replaced. The fan relay and coolant temperature sensors can be broken if your engine overheats and fails. You run the chance of having another seized engine instead of solving your initial issue until you address this main issue.

That is all for this article, in which we looked at long vs. short block engines. Nonetheless, the answers to the following questions have been discussed:

  • What are long and short blocks?
  • Which warranty is longer and better?
  • What are the differences between the two?
  • How much does long and short block cost?
  • Which is better, the long or short block?

Hope it was helpful. If so, kindly share it with others. Thanks for reading; see you around!

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