Built FA20 Long Block: A Complete Buyer's Guide
Making more horsepower is easy. Making reliable horsepower is the real challenge. Anyone can bolt on a bigger turbo and turn up the boost, but a stock FA20 will eventually protest—often with a loud bang. This is why a built FA20 long block is about more than just chasing a dyno number; it’s about creating a durable engine that can handle the stress you throw at it, day after day. It’s an investment in peace of mind. This guide covers everything from the essential components to the critical break-in process, ensuring your high-performance engine is built to last.
Key Takeaways
- A Built Engine is Your Foundation for Reliable Power: A professionally built FA20 long block isn't just for chasing high horsepower; it's about creating a durable platform. By replacing weak factory parts with strong forged internals, you get an engine that can safely handle significant power gains without sacrificing dependability.
- Budget for the Entire System, Not Just the Block: To get the performance you're paying for, you must account for essential supporting modifications. A complete build plan includes upgrades to the fuel system, cooling system, and the right turbo, plus professional installation and tuning costs.
- Your Responsibility Begins After Installation: The long-term health of your built engine depends on proper care. A meticulous break-in period, a more frequent maintenance schedule, and constant monitoring of your engine's vitals are non-negotiable steps to protect your investment.
What is a Built FA20 Long Block?
If you're looking to push your Subaru WRX or BRZ past its factory limits, you've probably heard the term "built long block." It’s the go-to solution when your power goals exceed what the stock engine can safely handle. Think of it as the foundation for serious performance—an engine re-engineered from the ground up with stronger components designed to handle the stress of significant horsepower gains. A built FA20 long block is what turns ambitious build goals into a reliable reality, providing the strength needed to support a larger turbo, aggressive tuning, and higher power levels without the constant worry of catastrophic failure.
Breaking It Down: Core Components and Forged Internals
So, what exactly are you getting? A "long block" is a nearly complete engine. It includes the core components—the engine block, crankshaft, connecting rods, pistons, and cylinder heads—all professionally assembled and timed. The key difference is in the "built" part, which means it contains forged internals. Unlike the cast parts in your stock engine, forged pistons and rods are created under immense pressure, making them incredibly dense and strong. This process gives them the resilience to withstand the intense heat and force that come with making big power, laying the groundwork for a build that can reliably handle 600 horsepower and beyond.
Built vs. Stock: What's the Real Difference?
The primary difference between a built and a stock FA20 comes down to strength and reliability under pressure. The factory connecting rods are the well-known weak link in a stock FA20 engine. When you start adding performance parts like a bigger turbo to push past the 350-400 horsepower mark, those stock rods are living on borrowed time. A built long block replaces these and other critical components with forged parts that won't bend or break under increased power. This isn't just about chasing a higher horsepower number; it's about creating reliable power. You get the peace of mind that your engine can handle the demands you place on it, whether on the track or the street.
Why Go with a Built FA20 Long Block?
Deciding to upgrade to a built FA20 long block is a major step, but it’s often the most logical one for any owner serious about performance. While the stock FA20 is a capable engine, it has well-defined limits. A built long block isn't just about chasing massive horsepower numbers; it's about creating a durable foundation for reliable power, whether you're aiming for a spirited daily driver or a dedicated track car. It’s the difference between pushing your stock engine to its breaking point and building an engine that comfortably handles the power you want to make. This move transforms your vehicle by replacing the factory's compromises with components engineered specifically for stress and performance.
Pushing Past 400 HP: The Power Advantage
The stock FA20 engine is great from the factory, but if your goals include a larger turbo and significantly more power, you’ll quickly hit a wall. Most tuners agree that the safe limit for a stock FA20 is around 400-450 horsepower. Pushing beyond that is a gamble. If you want to make serious power, you have to build the engine. The factory internals simply weren't designed for the increased stress. A professionally built FA20, on the other hand, is engineered to handle that abuse. With forged pistons, rods, and other strengthened components, a properly assembled long block can reliably manage power levels well over 600 horsepower, giving you the headroom to install the performance parts needed to achieve your goals.
Built for Battle: Reliability Under Stress
One of the biggest misconceptions is that built engines are less reliable than stock ones. The truth is, a professionally built engine is far more reliable than a stock engine pushed beyond its intended limits. The factory connecting rods in the FA20 are known weak points and are often the first components to fail when you add significant power. A built long block replaces these and other vulnerable parts with forged components designed to withstand intense heat and pressure. This isn't just about making more power; it's about making reliable power. When paired with the right supporting modifications and professional engine tuning services, a built engine provides a robust foundation that won’t leave you stranded.
Smart Investment: The Long-Term Value
While the upfront cost of a built long block is significant, it’s a smart investment in your vehicle's future. The alternative—pushing a stock block until it fails—can be far more expensive. A catastrophic engine failure can damage other components like your turbo, exhaust, and intercooler, leading to a much larger repair bill. A professionally built engine from a reputable builder like Crawford Performance also comes with a 12-month/12,000-mile warranty, offering peace of mind that a modified stock engine simply can't provide. You’re not just buying parts; you’re investing in expert assembly, proven components, and the assurance that your high-performance engine is built to last.
Who Builds the Best FA20 Long Blocks?
When you’re ready to invest in a built engine, choosing the right builder is the most critical decision you’ll make. The market has several reputable shops, each with a unique approach to building the FA20. Your goal is to find a builder whose philosophy, component choice, and track record align with your performance goals and budget. Look for transparency in their process and a solid warranty to back up their work.
Crawford Performance: Our Approach to the FA20
We start with the understanding that the factory FA20 engine has inherent weaknesses, particularly its connecting rods. When you push for more power with upgrades like a larger turbo, these stock parts are the first to fail. Our solution is a meticulously assembled forged FA20 long block that replaces those weak points with robust, forged internals built to handle significant stress. We believe a professionally built engine, paired with the right supporting mods and maintenance, is far more reliable than a stock engine pushed beyond its design limits. It’s about creating a durable foundation for reliable power, whether you’re on the track or a backcountry trail.
A Look at IAG Performance
IAG Performance is another major name in the Subaru engine-building world. They are well-known for their "Stage" packages and offer complete, drop-in long blocks for the 2015-2021 WRX. Their engines typically arrive fully assembled and timed, which can simplify the installation process. A key feature of their offering is the use of 100% new parts, which means you don’t have to worry about sending in your old engine as a core. They utilize their own IAG-Spec forged internals, like H-beam connecting rods and forged pistons, designed to be much stronger than the original factory components and capable of handling increased power and boost levels.
Other Key Players in the Market
Beyond Crawford and IAG, several other respected builders specialize in the FA20 platform. When evaluating your options, remember that the ultimate goal is reliable power. A well-constructed forged FA20 can handle 600 horsepower or more, but achieving that number safely depends entirely on the quality of the build and the tune. For serious power goals, buying a long block with strong internals already installed by experts is the smartest path forward. No matter who you choose, ensure they have extensive experience with Subaru engines and can provide a comprehensive plan that includes the necessary engine tuning services to get everything running perfectly.
How Much Power Can a Built FA20 Handle?
This is the big question, isn't it? When you decide to invest in a built engine, you want to know its limits. The truth is, there isn't a single magic number. The amount of power a built FA20 can handle depends entirely on the quality of the components, the precision of the assembly, and the strength of your supporting modifications. A well-executed build is a balanced system where every part works in harmony.
The stock FA20 block is respectable, but it has its ceiling. Most tuners agree that the stock internals are safe up to around 350-400 horsepower. Pushing beyond that on a stock engine is asking for trouble. Once you cross that threshold, you enter the world of built motors, where forged internals and professional assembly become non-negotiable. The power potential climbs significantly from there, but each new level demands more from the engine and the components surrounding it. Let's break down what you can expect at different power targets and what it takes to get there reliably.
Starting Strong: Builds for 400-500 HP
This is the sweet spot for many enthusiasts and the first major step past the stock engine's limits. A build targeting 400-500 horsepower transforms your WRX from a fun daily driver into a seriously quick street car that can hold its own on the track. To achieve this reliably, the engine needs fundamental upgrades like forged pistons and stronger connecting rods. These core performance parts provide the strength needed to handle the increased cylinder pressures from higher boost. This power level offers a massive performance gain you can feel every time you touch the throttle, without sacrificing too much of the car's everyday usability.
Next-Level Power: Builds for 500-600+ HP
Entering the 500-600 horsepower range requires a more serious commitment to your build. This is where component quality becomes absolutely critical. A robust, well-built forged FA20 long block is the foundation for this power level, featuring top-tier pistons, rods, and often an upgraded crankshaft. However, the engine can't do it alone. To support this kind of output, you'll need a complete ecosystem of WRX upgrades, including a high-flow fuel system, a larger turbocharger, and an efficient intercooler to manage heat. When properly assembled and tuned, a high-quality built FA20 can comfortably live in this power range, delivering incredible performance for the street or dedicated track use.
Maximum Attack: Pushing Beyond 600 HP
For those chasing ultimate power, pushing the FA20 beyond 600 horsepower is possible, but it's a venture into the extreme. This territory is typically reserved for dedicated race cars and requires a no-compromise approach. Every single component, from the head studs to the bearings, must be of the highest possible quality. The block itself may require reinforcement, such as closed-decking, to handle the immense stress. At this level, expert engine tuning services are not just recommended; they are essential to keeping the engine together. While some builders may opt for an engine swap for practicality at these power goals, a meticulously built FA20 can still deliver, proving just how capable this platform can be.
Building the Full Package: Essential Supporting Mods
Dropping a built FA20 long block into your Subaru is a huge step, but it’s not the final one. To truly get the power and reliability you’re paying for, you need to address the systems that support the engine. Think of it like this: you wouldn’t put a world-class sprinter in worn-out shoes and expect them to break records. The same principle applies to your engine. Making big power safely requires upgrading key components that work together as a complete system.
To get the most out of your investment, you need to plan for a better fuel system, a more robust cooling setup, and the right turbo to match your goals. These aren't just suggestions; they are essential pieces of the puzzle. Neglecting them is the fastest way to jeopardize your new engine and leave a lot of performance on the table. A built engine can only perform as well as its weakest supporting part, and pushing a stock fuel pump or radiator with a 500 HP motor is a recipe for disaster. Let’s walk through what you need to create a balanced and powerful build.
Fueling the Fire: Upgraded Fuel Systems
Once you start making more power, your engine gets a lot thirstier. The stock fuel system is only designed to handle factory output, and it simply can’t keep up with the demands of a built motor. Pushing it too hard can starve the engine of fuel, leading to a lean condition that can cause catastrophic failure. To prevent this, you need to supply your FA20 with all the fuel it needs.
This means installing high-flow fuel injectors and a higher-capacity fuel pump. These components ensure your engine receives a consistent and adequate fuel supply, especially under heavy load. Upgrading your fuel system isn't just about making more power—it's a critical step for protecting your engine and ensuring it runs reliably for years to come.
Keeping It Cool: Cooling and Intercooler Upgrades
More power generates more heat. It’s a fundamental rule of performance, and managing that extra heat is vital to your engine's health. The factory cooling system is fine for a stock car, but it will quickly become overwhelmed when trying to cool a modified engine making 400, 500, or even 600 horsepower. Overheating can lead to detonation, warped components, and serious engine damage.
A high-performance aluminum radiator is one of the most important performance parts you can add. It significantly increases cooling capacity and efficiency. For turbocharged setups, a larger front-mount intercooler is also essential for cooling the compressed air before it enters the engine. Denser, cooler air means more power and a lower risk of detonation. An upgraded cooling system keeps temperatures stable, protecting your investment and allowing for consistent performance.
Choosing the Right Turbo for Your Build
The turbocharger is the heart of your power production, and your choice will define your car's personality. Selecting the right turbo is a balancing act between your ultimate horsepower goals and how you want the car to feel on the street or track. A massive turbo might produce huge peak numbers, but it could also come with significant lag, making the car less responsive for daily driving.
When you select a turbo, you’re committing to a full system. A larger turbo requires more fuel, a more efficient intercooler, and a less restrictive exhaust to work properly. It’s crucial to choose a turbo that complements your built FA20's capabilities and your supporting modifications. Whether you're building a responsive street car or an all-out track machine, the right turbo will bring all your WRX upgrades together to deliver the performance you’re looking for.
What's the Real Cost? Budgeting for Your Build
Planning a build is exciting, but it’s also a serious financial commitment. To get a clear picture of the total investment, you need to look beyond the sticker price of the long block itself. The engine is the heart of your build, but it’s just one piece of the puzzle. A realistic budget accounts for the engine, core charges, essential supporting modifications, and professional installation. Thinking through these costs upfront helps you plan a build that meets your power goals without any surprise expenses down the road. Let’s break down what you should expect to spend to get your FA20 ready for serious performance.
Understanding Base Engine Prices
When you start shopping for a built FA20, you’ll see a range of prices, but a high-quality, purpose-built short block capable of handling over 600 horsepower typically costs between $5,000 and $6,000. This price reflects the precision engineering and forged internal components required for that level of strength and reliability. Think of it less as a purchase and more as an investment in your car’s foundation. Paying for a properly built engine from a reputable builder means you’re getting a platform that can withstand the stress of high power, giving you peace of mind whether you're on the track or the street.
Core Charges and Deposits Explained
You'll likely encounter a "core charge" when buying a built engine. This is essentially a refundable deposit, usually around $3,000 for an FA20, that you pay upfront. The charge encourages you to send your old engine back to the builder. Once they receive your original engine and confirm it’s in acceptable condition, you get your deposit back. However, be aware that significant damage to your old engine, like a ruined crankshaft, could result in a partial refund or an additional charge. Factoring this potential cost into your budget from the start is a smart move that prevents any last-minute financial surprises.
Factoring in Mods and Installation Costs
A built engine needs a strong supporting cast to perform safely and reliably. To get the most out of your new long block, you’ll need to upgrade your fuel and cooling systems to meet the new power demands. An Air-Oil Separator is also a non-negotiable mod for protecting your engine from oil blow-by. These performance parts are critical for engine health. Unless you’re an experienced engine builder, you should also budget for professional installation and tuning services. Paying a trusted shop for assembly ensures everything is done right, preventing costly mistakes that could damage your new investment.
How to Choose the Right Built FA20 Long Block
Investing in a built FA20 long block is a major step toward achieving your Subaru's performance potential. But with several builders on the market, how do you know you're making the right choice? The answer goes far beyond the price tag. A reliable, high-horsepower engine is the sum of its parts, the skill of its builder, and the guarantee that stands behind it.
Making an informed decision means looking closely at three key areas: the quality of the internal components, the terms of the warranty, and the builder's reputation within the Subaru community. A cheap engine that fails prematurely is no bargain, and a powerful build without a warranty is a significant risk. This guide will walk you through what to look for in each of these areas, so you can confidently choose a long block that delivers the power you want and the durability you need for the road or track ahead.
Check the Specs: Component Quality Matters
The foundation of any powerful engine is the quality of its components. A "long block" is a nearly complete engine, including the block, crankshaft, connecting rods, pistons, and cylinder heads, all assembled and timed. When you see the term "forged internals," it means critical parts like the pistons and rods were created under immense pressure, making them incredibly strong and capable of handling intense heat and stress. This is non-negotiable for a high-performance build. A properly constructed FA20 can handle well over 600 horsepower, but only if the internal performance parts are up to the task. Always ask for a detailed build sheet and don't hesitate to research each component yourself.
Protect Your Investment: Understanding Warranties
A warranty is more than just a piece of paper; it’s a builder’s vote of confidence in their own work. Any reputable engine builder should offer a warranty, with a 12-month/12,000-mile policy being a common industry standard. Before you commit, read the fine print carefully. Understand what is covered and, more importantly, what could void your coverage. Actions like improper installation, using the wrong fluids, or a bad tune can easily negate your warranty, leaving you with a very expensive problem. Professional engine tuning services are essential not only for performance but also for protecting your investment and ensuring your new engine operates safely within its limits.
Who's Behind the Build? Reputation and Experience
The best parts in the world won't matter if they aren't assembled correctly. The builder's reputation and experience—specifically with the FA20 platform—are just as critical as the components themselves. Look for a shop with a long, proven history of building reliable Subaru engines. A transparent builder will be open about their assembly process, the tools they use, and the clean environment where the work is done. These details drastically reduce the risk of assembly errors and contribute to a more dependable engine. Do your homework: read reviews, check forums, and see what kind of Subaru WRX upgrades and results other customers are getting from the builder you’re considering.
Busting Myths About Built FA20s
When you start researching built engines, you’ll run into a lot of opinions and a few persistent myths. It’s easy to get overwhelmed by conflicting information, especially when you’re making a significant investment in your Subaru. Let’s clear the air and tackle some of the most common misconceptions about built FA20s so you can move forward with confidence.
Myth vs. Fact: Are Built Engines Unreliable?
Let’s address the biggest myth first: the idea that a built engine is a ticking time bomb. The truth is, a professionally built forged engine, with the right supporting parts and maintenance, can be significantly more reliable than a stock engine pushed beyond its limits. The factory FA20 is a great motor, but it was designed for a specific power level. When you start adding a bigger turbo and aggressive tuning, you’re asking stock components to handle stress they were never meant to endure. A built engine replaces those weak points with forged internals designed from the ground up to handle intense heat and pressure. It's built to last, even with hard use.
DIY vs. Pro Build: What's the Right Call?
The temptation to build your own engine is strong, especially if you enjoy turning wrenches. But this is one job where experience is everything. Assembling an engine involves incredibly precise measurements, tolerances, and processes. A small mistake during assembly can lead to catastrophic failure down the road. Unless you are a seasoned engine builder, having a trusted shop assemble your long block is the right call. Engines built and tuned by experts are the most reliable. A professional build prevents expensive mistakes, and a proper tune from experienced engine tuning services ensures all your new parts work together safely and efficiently.
Finding the Sweet Spot Between Power and Reliability
Building a powerful engine isn't just about chasing a dyno number; it's about making reliable power. A well-built forged FA20 long block can handle 600 horsepower or more, but achieving that level of performance safely requires a holistic approach. You can't just drop in a built motor and expect it to thrive without the right support system. To keep the engine healthy, you must upgrade your cooling system, fuel system, and oil management. An Air-Oil Separator (AOS) is non-negotiable for preventing oil contamination and detonation. These supporting performance parts aren't optional—they are essential for creating a balanced and durable setup that you can enjoy for years to come.
The First Miles: Installation and Break-In
You’ve invested in a serious piece of hardware, and now it’s time to give it the best possible start. The first few weeks with your built FA20 long block are the most important. Proper installation, a careful break-in period, and diligent monitoring are what separate a reliable, high-power build from a costly headache. Think of this phase as laying the foundation for years of performance. Getting these steps right ensures your engine settles in correctly and is prepared to handle the power you plan to throw at it.
Why Professional Installation is Non-Negotiable
This is not the time for a weekend project in the garage. A built engine is a precision machine, and its installation demands an expert touch. We strongly recommend having a certified shop handle the installation. A professional technician has the specialized tools and experience to ensure every component is torqued to spec, all connections are secure, and the engine is primed correctly before its first start. More importantly, professional installation is often a requirement to keep your warranty valid. An expert installer will also work with your tuner to ensure the initial startup tune is loaded, protecting your engine from the very first rotation. This step is the single best piece of insurance for your investment.
The Break-In Process: Your First 1,000 Miles
Once the engine is in, the break-in period begins. This is a critical process where the new piston rings, bearings, and other internal components properly seat against each other. For the first 1,000 miles, you need to drive the car gently. This means keeping the RPMs below 4,000, varying your engine speed frequently, and avoiding full-throttle acceleration. Long highway trips at a constant speed are also off-limits. The goal is to let the new parts wear in together smoothly. After this period, a crucial oil and filter change is needed to clear out any initial metal particles. Following a proper break-in procedure is essential for the engine's long-term health and reliability.
Keeping an Eye on Your New Engine
A built motor requires an engaged owner. After the break-in, it’s important to monitor your engine’s vitals to catch any potential issues before they become serious problems. Using a Cobb Accessport or dedicated gauges to watch key parameters is a must. Pay close attention to oil pressure, oil temperature, coolant temperature, and your air-fuel ratio (AFR). These metrics are the language your engine uses to tell you how it’s feeling. Learning what’s normal for your setup allows you to spot inconsistencies early. This proactive approach to monitoring is a core part of owning a high-performance vehicle and is key to protecting your forged FA20 long block.
Protecting Your Power: Long-Term Care and Maintenance
You’ve made a significant investment in your Subaru’s performance, and now the focus shifts to protecting it. A built FA20 engine is a different beast than the stock version, and it requires a more attentive approach to maintenance. Think of it less as a chore and more as a partnership with your car. Proper long-term care ensures your engine delivers the reliable power you paid for, mile after mile. It’s about staying ahead of potential issues and keeping your build in peak condition, whether you’re on the track or the trail. This isn’t just about following rules; it’s about understanding what your high-performance engine needs to thrive. By adopting a proactive mindset, you can enjoy the full potential of your build for years to come. The initial break-in period is just the beginning. True longevity comes from consistent, informed care that addresses the increased stress and demands of a modified engine. This means being more in tune with your vehicle's sounds, smells, and performance data than ever before. It's a commitment, but one that pays off with every turn of the key.
Your New Maintenance Checklist
Your old maintenance schedule is officially retired. A built engine operates under much higher stress and heat, which means it needs more frequent attention. The most critical change is your oil change interval. A built engine needs fresh oil every 3,000 to 4,000 miles to keep its forged internals properly lubricated and cooled. Beyond oil, you’ll want to get in the habit of performing regular checks. Make it a weekly routine to pop the hood, check your oil and coolant levels, and look for any signs of leaks. This is also the time for constant monitoring of engine health, paying close attention to things like air-fuel ratio and boost levels to catch any deviations from the norm before they become problems.
How to Keep Your Warranty Valid
A warranty is your safety net, and keeping it active is straightforward if you follow the builder’s guidelines. The process starts before the engine is even in your car. Unless you’re a seasoned engine builder, the warranty will almost certainly require that a trusted shop handles the assembly and installation. This ensures every bolt is torqued to spec and all connections are secure. You’ll also need to strictly follow the specified break-in procedure and use the recommended oil and fuel types. Finally, a professional tune is non-negotiable. Skipping any of these steps can void your warranty and put your entire investment at risk. Always read the fine print and keep detailed records of all service and installation work.
Staying Tuned: Ongoing Performance Checks
Your engine’s tune is its operating system, and it’s crucial for both power and safety. A professional tune is a must right after installation, as it tells your engine’s computer how to manage the new components safely. But it’s not a one-time event. If you add other performance parts down the road, like a bigger turbo or new injectors, you’ll need a retune to account for those changes. To stay on top of your engine’s health day-to-day, install gauges to watch key metrics like oil pressure, oil temperature, and air-fuel ratio. These gauges are your early warning system, helping you spot problems early. This allows you to shut the car down before minor issues turn into catastrophic failures.
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Frequently Asked Questions
What's the difference between a long block and a short block? Think of a short block as the bottom half of your engine—it includes the engine block itself, along with the crankshaft, pistons, and connecting rods. A long block includes everything in the short block, plus the cylinder heads, camshafts, and valvetrain, all professionally assembled and timed. For a comprehensive performance upgrade like this, a long block is the most complete and reliable solution, as it ensures all major components are matched and assembled correctly.
Do I really need a built engine if I'm just aiming for 400 horsepower? While the stock FA20 can sometimes touch 400 horsepower, you're pushing it to its absolute limit. The factory connecting rods are the known weak point, and at that power level, you're living on borrowed time. A built engine isn't just about hitting a higher number; it's about creating reliable and sustainable power. Opting for a built long block provides the strength and peace of mind that your engine can handle that power consistently without the constant risk of catastrophic failure.
How does a built engine affect my car's daily drivability? A properly built and tuned engine can be perfectly suitable for daily driving. The key is the professional tune that accompanies the build. A good tuner can ensure the car is smooth and responsive at low speeds while still delivering incredible power when you want it. The choice of turbocharger also plays a big role. A setup designed for a responsive powerband will feel much better on the street than one built only for maximum horsepower at the top of the rev range.
Why is an Air-Oil Separator (AOS) so critical for a built FA20? An Air-Oil Separator is essential because high-performance engines produce more crankcase pressure, which can push oil vapor into your intake system. This oil contaminates the air-fuel mixture, effectively lowering your fuel's octane rating and increasing the risk of detonation—a major engine killer. An AOS intercepts this oil vapor, separates the oil, and returns it to the engine, ensuring only clean air enters the combustion chamber. It's a vital piece of insurance for any built motor.
What's the single most important thing to remember during the break-in period? Patience is key. The most critical task during the first 1,000 miles is to vary the engine speed constantly without putting it under heavy load. This means avoiding highway cruising at a single RPM and resisting the urge to go full throttle. This process allows the new piston rings to seat properly against the cylinder walls, which is absolutely essential for your engine's long-term compression, power, and oil consumption. Rushing this step can compromise the entire build.