3 Best FA24 Engine Builders for Serious Power

There’s a common fear in the performance world that big horsepower automatically means poor reliability. Many enthusiasts hesitate to build their FA24, worried they’ll be trading daily drivability for a fragile track toy. The truth is, you can have both. A professionally built engine doesn’t just make more power; it’s engineered for greater strength and durability than the factory version. The key is choosing a builder who understands this balance. This guide will help you find the best FA24 engine builder who prioritizes longevity alongside performance, ensuring your investment results in a car that is both thrilling and dependable.

Key Takeaways

• A Built Engine is a Foundation for Power: Building your FA24 means reinforcing it with stronger internal components. This creates a durable base that reliably supports significant horsepower gains, whether you start with a short block or a more complete long block.
• Your Builder is a Critical Partner: Choosing the right engine builder is essential. Prioritize shops with proven FA24 expertise, transparency about the parts they use, a strong warranty, and in-house tuning services for a cohesive result.
• Budget for a Balanced System: The engine is just one piece of the puzzle. To achieve your goals safely, you must also budget for supporting upgrades like a turbo, fuel system, and professional ECU tuning, which are necessary to handle the increased power.

Getting to Know the FA24 Engine

Before you dive into planning a high-horsepower build, it’s smart to get familiar with the heart of your car: the FA24 engine. This 2.4-liter boxer engine has quickly become a favorite in the Subaru community, and for good reason. It serves as a powerful and responsive base, but understanding its design and how it differs from its predecessors is the first step toward making informed decisions about your performance goals. Knowing the fundamentals will help you have more productive conversations with your engine builder and choose the right path for your vehicle.

FA24 vs. FA20: What Are the Key Differences?

The most significant difference between the FA24 and the older FA20 is the displacement. The FA24’s larger 2.4-liter size gives it a clear advantage in producing more power and torque right out of the box. Think of it as having a better starting point for any build. This isn't just about size, though. The FA24 incorporates a stronger design and more advanced components that improve both performance and reliability under stress. For enthusiasts looking to make serious power, the FA24 is a much more capable platform, handling modifications with greater ease than its 2.0-liter predecessor. This robust foundation is why so many tuners are excited about its potential for incredible performance parts.

Which Subaru and Toyota Models Have the FA24?

You'll find the FA24 engine in some of the most popular enthusiast cars on the market today. Subaru equipped the 2022 and newer WRX models with the turbocharged FA24DIT, giving the iconic sedan a much-appreciated bump in performance. On the naturally aspirated side, the FA24 powers the second-generation Subaru BRZ and its sibling, the Toyota GR86. This shared platform has been praised for its responsive and engaging driving dynamics. If you own one of these models, you already have an excellent foundation for a performance build. Investing in Subaru WRX upgrades can take what’s already great about this engine and turn it into something truly special for the street or track.

Why Build Your FA24 Instead of Replacing It?

When you start pushing your Subaru or Toyota for more power, you’ll eventually meet the limits of its stock components. If you’re facing engine issues or simply want to build a car that can handle serious performance, you have a choice: replace the engine with another stock one, or build it for strength and power. While a stock replacement gets you back on the road, a professional build prepares you for the future.

Building your FA24 is about transforming it from a capable factory engine into a robust powerhouse tailored to your goals. It involves reinforcing the engine's core with stronger internal components designed to handle significantly more stress than the original parts. This proactive approach not only unlocks massive performance potential but also adds durability, giving you the confidence to push your car on the track or trail without worry. It’s an investment in making your vehicle exactly what you want it to be.

Where the Stock FA24 Falls Short

The FA24 is a solid engine from the factory, but it wasn't designed for the high-horsepower demands of serious enthusiasts. Many owners find its limitations frustrating, especially when they start adding performance modifications. One of the main concerns is longevity under stress. While older Subaru engines were famous for their durability, the stock FA24’s internal components can become a weak point when you increase boost and power. For anyone looking to create a truly high-performance vehicle, addressing these factory shortcomings isn't just an option; it's a necessity for reliable power.

The Power of a Professionally Built FA24

A professionally built FA24 is more than just an engine; it’s a completely re-engineered heart for your vehicle. Expert builders disassemble the engine and replace critical components with forged and billet parts that are vastly stronger than the stock versions. This process often involves using top-tier performance parts to create an engine that can reliably handle immense power and torque. By reinforcing the block and strengthening the rotating assembly (pistons, rods, and crankshaft), a built motor provides a durable foundation for whatever you throw at it, from aggressive track days to demanding overland adventures.

Realistic Performance Gains to Expect

The results of a built FA24 are immediate and impressive. Even before a custom tune, you can see gains of around 50 horsepower and 70 ft-lb of torque at the wheels, thanks to improved efficiency and stronger components. However, the real magic happens after the build is complete. With professional engine tuning services that optimize fuel, air, and spark for your new setup, those numbers can climb even higher. It’s realistic to see an additional 70 horsepower and 100 ft-lb of torque, turning your car into a completely different machine. These aren't just numbers on a chart; they represent a dramatic change in acceleration and driving experience.

How to Choose the Right FA24 Engine Builder

Choosing an engine builder is one of the most important decisions you’ll make for your vehicle. This isn’t just a transaction; it’s the start of a partnership with a team you’re trusting to create the heart of your car. The right builder will not only deliver the power you’re looking for but also provide the reliability and support you need to enjoy it with confidence. A poorly chosen one can lead to endless headaches, unexpected costs, and a car that spends more time in the shop than on the road.

So, how do you separate the experts from the amateurs? It comes down to asking the right questions and knowing what to look for. You need a builder who understands the FA24 platform inside and out, uses only high-quality parts, and stands behind their work with a solid warranty. They should also be able to provide the expert engine tuning services needed to make all those new components work together perfectly. Finally, clear and consistent communication is non-negotiable. Let’s walk through the key criteria to help you find a builder you can trust.

Do They Have Proven FA24 Platform Experience?

The FA24 is a fantastic engine, but it has its own unique personality compared to the older EJ or even its FA20 predecessor. When you’re vetting a builder, their specific experience with the FA24 platform should be at the top of your list. Ask them directly about the FA24 builds they’ve completed. Can they speak to its common failure points and how their build process addresses them? A shop that primarily works on other engines might not understand the specific tolerances, oiling system quirks, or assembly procedures required to make an FA24 reliable at high power levels. True expertise means they’ve already done the research and development, so you’re not paying for their learning curve.

Insist on Quality: A Look at Parts and Sourcing

A built engine is only as strong as its weakest component. A top-tier builder will be transparent about the parts they use and why they choose them. Many of the best shops, including Crawford Performance, engineer their own proprietary performance parts designed to solve specific platform weaknesses. They also source components like pistons, connecting rods, and bearings from other industry-leading brands known for their quality and durability. Don’t be afraid to ask for a detailed parts list for your build. If a builder is vague about where their components come from or pushes for no-name alternatives to save a few dollars, it’s a major red flag. Quality parts are your best insurance against premature failure.

What Happens After the Build? Warranty and Support

Once your engine is built and the final payment is made, the relationship with your builder shouldn't end. Post-build support is what separates a good shop from a great one. Before you commit, get a clear understanding of their warranty. What does it cover, and for how long? For example, we stand behind our work with a comprehensive 12-month/12,000-mile warranty because we are confident in our process and parts. You should also ask about their typical build timeline and how they handle support after you get your car back. A reputable builder will be there to answer questions, help with break-in procedures, and provide guidance for the life of your engine.

Can They Provide Expert Tuning and Customization?

Assembling a short block is one thing; creating a complete, reliable performance package is another. Your built engine needs a precise tune to safely make power and run correctly. A builder who also offers expert tuning services can ensure your entire setup is cohesive. They can help you select the right supporting modifications, from turbochargers to fuel systems, that align with your goals. Whether you’re building a high-revving track car or a torque-focused daily driver, the builder should be able to customize the build and the tune to match your specific needs. This holistic approach is key to getting the most out of your investment.

Will They Keep You in the Loop? Communication Matters

An engine build is a complex and often lengthy process. A builder who leaves you in the dark is a recipe for anxiety and frustration. Great communication is a sign of a professional and well-run operation. Your builder should provide regular updates on the progress of your build, complete with photos and detailed explanations of the work being done. They should be easy to reach and willing to answer your questions promptly. This transparency builds trust and makes you feel like a part of the process. If you’re struggling to get a response from a shop during the initial quote phase, imagine how difficult it will be once they have your engine.

A Look at the Top FA24 Engine Builders

Choosing the right hands to build your engine is one of the most critical decisions you'll make. The FA24 platform has attracted some serious talent, and a few shops have consistently stood out for their expertise, quality, and results. When you're investing in the heart of your Subaru, you want a builder with a proven track record. We'll look at three of the top names in the business, each known for their unique approach to extracting reliable power from the FA24 and creating complete performance parts ecosystems.

1. Crawford Performance

With a legacy built on decades of Subaru performance, we at Crawford Performance bring a unique level of expertise to the FA24 platform. Our philosophy is simple: build engines that deliver incredible power without sacrificing the reliability you need for the track, trail, or daily commute. We use a meticulous, hands-on process, selecting only premium components that meet our exacting standards. This commitment to quality is why we can offer our industry-leading 12-month/12,000-mile engine warranty. Our engine tuning services are designed to perfectly complement our builds, ensuring every component works in harmony to create a responsive, powerful, and durable machine ready for anything you throw at it.

2. IAG Performance

IAG Performance is a well-known name in the Subaru community, specializing in high-performance parts and complete engine builds. They offer a wide array of components, from individual engine parts to fully assembled short blocks and long blocks for the FA24. Their reputation is built on engineering parts designed to handle significant power increases while maintaining reliability. For many enthusiasts looking to get more from their Subaru, IAG has become a go-to source for robust engine solutions. Their extensive catalog provides options for various stages of modification, catering to a broad spectrum of performance goals.

3. Out Front Motorsports

Out Front Motorsports is recognized for its work on the FA24 engine, particularly with their FB24 long block. This build is designed as a powerful upgrade for the BRZ and GR86 platforms. The engine is constructed with high-quality internals, including specialized bearings, rods, and pistons, and is paired with enhanced cylinder heads. Out Front Motorsports markets this engine as a straightforward "drop-in" solution, which simplifies the installation process for owners and shops. This focus on a complete, ready-to-install package makes them a notable option for those looking for a comprehensive engine replacement that delivers a major performance improvement.

Short Block or Long Block: Choosing Your FA24 Build

When you decide to build your FA24, one of the first big questions you'll face is whether to go with a short block or a long block. This isn't just a technical detail; it's a fundamental choice that shapes your entire project, from the budget to the final power output. Think of it as choosing the foundation for your house. A short block gives you a rock-solid base, while a long block provides the base plus the framework, ready for the finishing touches.

The right choice depends on your specific goals, the condition of your current engine components (like the cylinder heads), and how hands-on you want to be with the rest of the build. Both paths can lead to incredible performance, but understanding the difference is key to making a decision you'll be happy with down the road. We'll break down what each option includes so you can confidently choose the right starting point for your ultimate FA24 build. These builds are the cornerstone of many high-quality performance parts installations and set the stage for everything else you do to your car.

What Is a Short Block Build?

A short block is the heart of your engine's bottom end. It consists of the engine block itself, fitted with a crankshaft, connecting rods, and pistons. When you get a built short block, you're getting a foundation engineered to handle far more power than the stock components. This is the perfect route if your factory cylinder heads are still in great shape or if you have plans for a custom head setup. By starting with a robust short block, you ensure the core of your engine is ready for whatever power you throw at it, giving you a reliable base for your engine tuning services.

What Is a Long Block Build?

A long block takes the short block and builds upon it. It’s a more complete assembly that includes the short block plus the cylinder heads, camshafts, and valvetrain components. Essentially, it's a nearly complete engine, ready to be installed and fitted with your accessories. Choosing a long block is an excellent way to get a professionally matched and assembled package. The builder ensures every component, from the pistons to the valves, is designed to work together seamlessly. This option saves you time and eliminates the guesswork of sourcing and assembling the top end yourself, providing a comprehensive solution for your build.

Matching the Build Type to Your Power Goals

So, how do you choose? It all comes back to your power goals. If you're aiming for a significant but moderate power increase and your stock heads are in good condition, a built short block provides the necessary strength without replacing parts you don't need to. However, if you're chasing serious horsepower, a long block is almost always the answer. High-power builds require heads that can manage much greater airflow. A built long block comes with ported cylinder heads and an upgraded valvetrain, all optimized to support your ambitious goals and ensure your entire engine assembly is balanced and durable for the track or street. These complete packages are essential for many Subaru WRX upgrades.

How Much Does an FA24 Engine Build Cost?

Building your FA24 is a serious investment in your vehicle’s performance, and the final cost can vary quite a bit. The price depends on your power goals, the components you choose, and whether you opt for a short block or a more complete long block assembly. Think of it less as a single price tag and more as a budget you build based on your specific needs. A build designed for 400 horsepower will have a different price point than one engineered to handle 600 horsepower or more.

This decision is one of the most exciting parts of modifying your car, but it’s also one that requires careful financial planning. To give you a clear picture, we’ll break down the costs associated with the engine itself, the factors that drive the price up or down, and the extra expenses you’ll want to plan for to complete your project. Understanding the full financial scope from the beginning helps ensure your build goes smoothly and you end up with the reliable power you’re looking for.

Breaking Down Short Block vs. Long Block Costs

The first major decision that impacts cost is choosing between a short block and a long block. A short block is the engine's foundation, typically including the block, crank, rods, and pistons. Prices for a performance FA24 short block generally range from $4,500 to $18,000. The wide range reflects the quality of the internal components and the power level they are built to withstand.

A long block is a more complete package, building on the short block by adding cylinder heads, camshafts, and the valvetrain. This option gets you much closer to a drop-in solution. FA24 long blocks usually run from about $10,500 to $19,500. The final price depends on the extent of the build, such as whether it includes ported heads or upgraded cams. The choice really comes down to your budget and how much of the assembly you want handled by a professional builder.

Factors That Influence the Final Price

Several key factors determine the final cost of your built engine. Your horsepower target is the biggest driver; pushing for higher numbers requires stronger, more expensive internal performance parts like forged pistons and billet connecting rods. The specific brands you and your builder choose for these components also play a significant role in the overall price.

Labor and expertise are also part of the equation. You're paying for the skill, precision, and time it takes to assemble an engine to exacting tolerances. Finally, lead times can affect the process. While some parts may be readily available, a fully custom engine is often built to order and can take several weeks to complete, depending on the builder’s schedule and parts availability.

Don't Forget These: Budgeting for Extra Costs

The cost of the engine block is just one piece of the puzzle. To support your newly built motor, you'll need to budget for several other critical items. These often include a larger turbocharger, an upgraded fuel system, a more efficient intercooler, and a performance exhaust to handle the increased output. These supporting Subaru WRX upgrades are not optional; they're necessary to safely achieve your power goals.

You also need to account for installation labor, shipping freight for the engine, and essential fluids and gaskets. Most importantly, a professional engine tuning service is mandatory. A proper tune ensures your engine runs reliably and delivers the performance you paid for. Forgetting these items can quickly add thousands to your total project cost, so it's best to plan for them from the start.

Essential Upgrades to Complement Your Built FA24

A built FA24 engine gives you a rock-solid foundation for making serious power, but it’s only the first step. To truly get the most out of your investment, you need to surround that built block with supporting modifications that can handle the increased demands. Think of it like building a high-performance team; your built engine is the star player, but it needs a strong supporting cast to win.

These upgrades work together to ensure your engine can breathe, get enough fuel, and operate efficiently under pressure. Skipping these components means leaving a significant amount of power on the table and potentially risking the health of your new engine. From increasing airflow to dialing in the tune, each of these parts plays a critical role in creating a balanced, reliable, and powerful setup. Let’s walk through the essential upgrades you’ll need to complete your build.

Turbocharger Kits

The stock turbo on the FA24 is great for daily driving, but it quickly becomes a bottleneck when you’re chasing higher horsepower. A larger turbocharger is one of the most effective ways to make more power. It forces a greater volume of air into your built engine, which, when combined with more fuel, results in a bigger bang. This upgrade is especially noticeable in the mid-to-high RPM range, where the stock turbo starts to lose steam. Choosing the right turbo from a range of performance parts depends on your power goals, but it’s a fundamental piece of the puzzle for any serious FA24 build.

Intake, Exhaust, and Intercooler Upgrades

If a bigger turbo is forcing more air in, you need to make it easier for that air to get into and out of the engine. A high-flow intake system reduces restriction, allowing the turbo to pull in cool, dense air more efficiently. On the other side, a performance exhaust system lets exhaust gases escape faster, reducing back pressure and helping the turbo spool quicker. An upgraded intercooler is just as important. It cools the compressed air from the turbo before it enters the engine, which prevents detonation and allows for more aggressive tuning. These Subaru WRX upgrades work together to maximize engine efficiency.

ECU Tuning and Accessport Solutions

All these new hardware upgrades won’t do you any good without a way to make them work together. This is where ECU tuning comes in. A professional tune adjusts your engine’s fuel and ignition timing maps to optimize performance for your specific combination of parts. It’s the brain of the operation, ensuring your engine runs not just powerfully but also safely. Tools like the Cobb Accessport provide a user-friendly platform for this process. Proper engine tuning services are not optional; they are absolutely essential for unlocking the full potential of your built FA24 and protecting your investment.

Upgraded Fuel Injectors and Fuel Systems

More air from your new turbo requires more fuel to maintain the correct air-fuel ratio. The stock fuel system can’t keep up with the demands of a modified, high-horsepower engine. Upgrading to higher-flow fuel injectors and a more robust fuel pump is critical for delivering the volume of fuel your engine needs. This prevents a lean condition, where there isn’t enough fuel for the amount of air, which can lead to catastrophic engine damage. Investing in quality fuel system components, like those found in Subaru STI upgrades, is a necessary safety measure that also ensures you can extract every bit of power from your setup.

The Other Side: What to Consider Before You Build

Chasing big power numbers is exciting, but a successful engine build is about more than just what happens on the dyno. It’s a serious commitment that changes your relationship with your car. Before you take the leap, it’s important to understand the practical realities of owning and driving a vehicle with a built FA24. Thinking through these details ahead of time ensures there are no surprises, so you can fully enjoy the new capabilities of your Subaru.

From your factory warranty to your daily driving habits, a built motor impacts almost every aspect of vehicle ownership. Being prepared for these changes is the key to a rewarding and stress-free experience. Let’s walk through what you need to consider, from the paperwork and supporting mods to the new maintenance routine your high-performance engine will demand. This isn't meant to discourage you; it's about making sure you're building your dream car with your eyes wide open.

How a Build Affects Your Warranty and Insurance

First, let's address the big one: your warranty. Modifying your engine with aftermarket performance parts will almost certainly void your vehicle’s factory powertrain warranty. Manufacturers are not responsible for covering failures that can be traced back to non-original components or tuning. It's also a good idea to have a conversation with your insurance provider. While many standard policies cover modified vehicles, you may need to add a special endorsement to ensure your expensive new engine and other upgrades are actually covered in case of an accident or theft. Being upfront with your insurer prevents potential claim denials down the road.

The Ripple Effect: Other Mods You Might Need

A built FA24 engine creates a lot more power, and the rest of your car needs to be able to handle it. Think of it as a chain; your engine is just one link. To avoid breaking the weakest link, you’ll need to plan for supporting modifications. A stronger clutch is often non-negotiable for manual transmissions. Your braking system might need an upgrade to safely slow down from higher speeds. You may also want to consider suspension and drivetrain components, like axles and driveshafts, to effectively transfer that newfound power to the pavement without issue.

Living With a Built Engine: Fuel and Maintenance Needs

Your built engine will have different daily requirements than a stock one. Most high-compression, high-horsepower builds require premium, high-octane fuel (91 or 93) to prevent engine knock and perform optimally. You can’t just fill up with regular anymore. Your maintenance schedule will also become more rigorous. More frequent oil changes with high-quality synthetic oil are essential for longevity. You’ll also want to keep a closer eye on fluid levels, spark plugs, and filters. Partnering with a shop that offers expert engine tuning services is crucial, as they will set the parameters that dictate your fuel and maintenance needs.

Is Crawford Performance the Right Builder for You?

Crawford Performance is a name that comes up time and again in conversations about elite Subaru performance, and for good reason. With a legacy built on pushing the limits of the boxer engine, they have established themselves as a premier builder, especially for the FA24 platform. Their work is inspired by legends like Ken Block and is trusted by enthusiasts who demand the best for both track and trail. If you're looking for a builder with a deep history of proven results and a commitment to quality that extends long after the build is complete, Crawford deserves your serious consideration. Let's look at what sets them apart and how they provide peace of mind for your investment.

The Crawford Performance Difference

What makes a Crawford-built engine special? It comes down to decades of focused experience. With over 20 years dedicated to mastering Subaru performance, their team possesses an intimate knowledge of the FA24 engine. They don’t just assemble parts; they re-engineer solutions. This means using advanced techniques and sourcing only high-quality components to ensure every build is powerful, reliable, and durable. Their meticulous attention to detail is evident in everything from their custom builds to their extensive catalog of performance parts. This comprehensive approach ensures that every element of your build works in perfect harmony to meet your specific performance goals.

Peace of Mind: The Crawford Performance Warranty

Investing in a built engine is a significant decision, and one of the biggest questions is always about reliability. Crawford Performance addresses this head-on with their unique 12-month/12,000-mile engine warranty. This isn't just a piece of paper; it's a statement of confidence in their craftsmanship and the quality of their work. This warranty covers defects in materials and workmanship, giving you a crucial safety net for your investment. For an enthusiast pushing their vehicle with expert engine tuning and high-performance parts, knowing the builder stands firmly behind their product is invaluable. It allows you to enjoy the power you’ve paid for without the constant worry.

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Frequently Asked Questions

Is building my FA24 really necessary if I just want a little more power? Not always. If your goals are modest, like the gains from a simple intake, exhaust, and a basic tune, your stock engine is perfectly capable. An engine build becomes necessary when you want to make a significant leap in power that the factory internals can't safely support. It's the right move when you plan to add a larger turbo or push for horsepower numbers that would risk the long-term health of a stock motor.

What's the simplest way to understand the difference between a short block and a long block? Think of a short block as the strong, reinforced foundation of your engine, containing the block, pistons, and rods. It's the perfect choice if your cylinder heads are in great shape and you want a solid base for your build. A long block includes that foundation plus the cylinder heads and valvetrain, making it a nearly complete engine. It's a great option for a comprehensive, professionally matched package where all components are designed to work together from the start.

Why is a professional tune so important after an engine build? A built engine is a collection of high-performance hardware, but a tune is what tells it how to work. Without a professional tune, your new engine won't run correctly, and you could even damage it. The tuning process adjusts the fuel, ignition, and timing parameters to match your new components, ensuring the engine makes power safely and efficiently. It’s the final, critical step that brings your entire investment to life.

Besides the engine itself, what's the most important supporting upgrade I should budget for? While a bigger turbo and better cooling are essential, the fuel system is arguably the most critical supporting modification. A built engine making more power requires significantly more fuel. Upgrading your fuel pump and injectors is not just about making power; it's about protecting your engine. An inadequate fuel system can cause the engine to run lean, which can lead to catastrophic failure in seconds.

Will a built engine be less reliable for daily driving? Quite the opposite, as long as it's done right. A professionally built engine is engineered with stronger components designed to handle stress far better than the stock parts. When paired with a proper tune and a consistent maintenance schedule, it can be incredibly durable for daily use. The unreliability myth usually comes from poorly executed builds or neglecting the required maintenance, not from the concept of a built engine itself.