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What Are CNC Block Guard

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The CNC block guard can successfully keep your engine block safe in extreme conditions. Due to the high functioning capability, people are increasingly leaning towards the CNC block guards. Are you worried about your engine block’s safety?

The CNC block guard can be the perfect solution for you. Read through this article to get the answer to all your basic queries about CNC block guards.

CNC block guardCNC block guard red

Understanding CNC Block Guard

CNC block guards are CNC machined mechanical units. They work as a functional unit to support the top wall of the engine block. You can fit this unit on the top of the cylindrical bore of an engine block.

These units are manufactured from high-strength, corrosion-resistant, and durable materials. So, ultimately, you can reinforce the strength of the top cylindrical wall of the block.

During extreme applications, the cylinder wall experiences very high stress. Due to the reinforced strength provided by the CNC block guards, you can reduce the risk of crack failure in your engine.

Manufacturers use computer-aided automatic machines to create CNC block guards. The computer numerical control machines or CNC machines are excellent in manufacturing customized components following specific and accurate design.

The Purpose Of Using A CNC Block Guard

The primary purpose of using a CNC block guard is to keep your engine block safe during extreme conditions.  It protects the cylindrical block wall from cracking failure.

At high RPM, the pistons move up and down inside the cylindrical block at a tremendous speed. The same thing occurs when you perform different kinds of high boost applications.

So, an immense amount of heat is generated inside the cylindrical block. In normal conditions, your engine’s cooling system is sufficient to reduce the temperature to balanced levels.

But during extreme conditions, the cooling system is not sufficient. So, the walls of the cylindrical bore tend to expand at high temperatures. This creates high internal stress on the walls.

The weakest point is created at the top-most part of the block. If the engine block exceeds limit levels, this might lead to cracking. This is why you should use CNC block guards.

There is a gap between the exterior portion of the cylinder wall and the block. Once you install the CNC block guards, it will fill up this gap. Ultimately, the CNC block guard supports the cylinder wall to reduce flexing.

If you can ensure precise design and fitting, the block guard will fill up this gap much more efficiently. So, the CNC block guard can serve its purpose more smoothly. 

CNC Block guard machining

The Impact of Block Guard on Your Engine Power

The block guard not only keeps your engine safe but also boosts up the power of your engine. The CNC block guards help to maintain the heat levels of your engine at balanced levels. With heat levels at check, the efficiency of the engine’s output power increases at significant levels.

The cylinder wall of the engine block has different spots that are weaker than other areas. These areas are called hot spots. Compared to other areas, the temperature in these areas tends to increase to intense levels.

The CNC guard blocks have properly designed watering holes. The manufacturers design the positioning of these holes based on a substantial amount of calculation and research to achieve the most optimum output.

These holes allow efficient circulation of the water and coolant in the open deck design. The coolant flow also covers the critical hot spot areas and keeps the temperature levels at balanced levels.

Additionally, the CNC block guard increases the surface area of the bore. It transfers more heat from the bore to the coolant.

Another advantage that the CNC block guard provides is the ability of the engine to run in extreme conditions. Even at the highest levels of RPM, it keeps the cylinder walls safe from high stress. So, you can extract the highest power from the engine without worrying about its damage.

The CNC block guard contributes to these factors to substantially keep the temperature levels in check, So all the engine components can perform a smoother operation. This increases the output efficiency in each of their performances, leading to a boosted engine power.

Extract The Highest Power From Your Engine Using The CNC Block Guard

Best Material For An Engine Block

Cast iron and aluminum alloys are considered as the best materials for an engine block. Each material is better in some unique properties. You must consider some factors for selecting the material best suited for what functionality you want to focus on.

Focus on the properties that will assist the engine block to work as an efficient functional unit.

First, focus on strength. The engine block works as the foundation for the crankshaft, piston cylinders, and other engine components. When the engine operates, the pistons shift up and down at a very high speed.

So, you must choose the material with a high strength property. Of the two materials, cast iron is more robust than aluminum alloy.

Next, consider the material that is more resistant to wear. The engine block undergoes heavy frictional force. So, the unit is vulnerable to wear. In this regard, cast iron is stronger than aluminum alloy.

Following that, focus on the heat-conducting capacity of the material. The combustion process generates very high heat. You must make sure to efficiently remove the generated heat from the inside to the outside cooling system.

Aluminum alloys have a higher heat-conducting capacity. It will give you an edge over cast iron to quickly transfer the heat generated inside the engine block.

Another additional material property is specific weight. Aluminum alloys are lighter than cast iron. With aluminum alloys, you can focus on the weight reduction feature of the engine block.

Considering these factors, manufacturers used cast iron to manufacture engine blocks up to the late 80s and early 90s. Now, manufacturers consider aluminum alloys as the best material due to their better functioning properties in critical aspects. So, they are using aluminum alloys to manufacture CNC block guards from the mid-90s until now.

Manufacturers also make a combination of both these materials for producing the main engine block with aluminum alloys and provide a layer of cast alloy on top. With this, you can satisfy all the influencing properties.

CNC block guard Car parts

Finishes Suitable for CNC Block Guards

Various suitable finishes confer advantages on CNC block guards, precision-engineered components used for engine block reinforcing. The oxide layer created by anodizing, a widely used method with aluminum block guards, provides improved corrosion resistance and the possibility of color selection. The advantages of powder coating are increased durability, corrosion resistance, and color options. Ceramic coatings are outstanding in terms of thermal tolerance, ideal for engines that perform well. Perfect for steel block guards, black oxide provides corrosion protection. Aesthetics also balance with performance as natural or bare metal options are available. Teflon or PTFE coatings reduce friction. The finish selection should be based on the application of the engine, materials and compatibility to deliver favorable performance and long lasting protection

CNC Machining Technology Used for Producing Block Guard

The CNC milling is the most convenient method of creating block guards, due to its exceptional accuracy, ability to work with a wide range of materials and time efficiency. It allows for the manufacture of block guards with complicated and customized patterns, ensuring they are snugly located inside engine blocks but consistent across runs. CNC milling machines are capable of working with a variety of materials, allow customization, and offer on-the-fly quality control. This technology eliminates material waste, minimizes production times and delivers block guards to very exact tolerances ans specifications thus making it the best choice for this key engine part.billet car parts 6

Benefits of Using A CNC Block Guard

You should use the CNC block guard if you want to ensure your engine’s safety at high boost applications. The engine block undergoes heavy abuse during the operational phase. You must secure the safety of the engine block with proper precautionary steps.

When the engine runs, the combustion reaction takes place inside the engine. A very high amount of heat is generated inside the engine. Significantly during high boost applications, the generated heat exceeds extreme levels.

All the metals respond to some specific properties. They tend to expand with the increase in temperature. So when an excessive amount of heat is generated inside the engine, the interior layer of the cylinder wall tries to expand. 

So, the wall experiences high internal stress. They tend to expand towards the existing gap at the exterior layer of the engine block. This is the most critical situation during high boost applications. During this time, the engine block becomes vulnerable to cracking.

The CNC block guard will perfectly fit into the gap. An additional piece will help reinforce the engine block and support it with additional durability.

The engine block is now ready to fight the high internal stress with the existing and added strength. So, you should use a CNC engine block. And you no longer have to worry about the safety of the engine.

The Durability of CNC Block Guards

When it comes to the question of durability, the CNC block guard can pass the ultimate test. 

The CNC block guard is made from aluminum alloy that can withstand high pressure. Since the pressure is distributed over a larger area, the engine block experiences less stress than before. This ensures the safety of the engine block due to the durability of the CNC block guard.

Additionally, aluminum alloys have an excellent ability to withstand wear. As a complementary unit of the engine component, the CNC block guard undergoes heavy friction. So, manufacturers use aluminum alloys to manufacture durable CNC block guards.

With these features, the CNC block guard continues to last for a long time, proving its durable characteristics.

CNC Block Guards Are Extremely Durable High Boost Applications Like Nitrous Oxide

Install A CNC Block Guard

Due to this superior level of precision, the CNC block guards perfectly fit in the engine block during the installation. It makes the installation process easier than block guards manufactured with other techniques.

It is simple and easy to install the CNC block guard. Just follow these simple steps:

  • Thoroughly clean the surface of the engine block over which you will install the CNC block guard. Most of the time, there is excess grease on this surface. Use a high-absorbing cloth to remove the grease or oil.
  • Determine the temperature of the engine during the operational phase.
  • First, heat the engine block until you reach the determined temperature. Then, heat the CNC block guard up to the determined temperature. This step is very important. If you install the CNC block guard at room temperature, additional internal stress will occur when the engine is running.
  • Place the CNC block guard aligning with the engine block.
  • Press the CNC block guard with slight pressure on the installation surface.
  • When it fits in, let the engine block and CNC block guard cool down following room temperature.
  • Once the installation is complete, hone the block if it’s necessary.

CNC block guard manufacture

Find The Best CNC Block Guard Manufacturer

Choosing the best manufacturer for a CNC block guard is critical to ensuring the best safety for your engine. When you are selecting the best manufacturer, you have to focus on different factors.

Ensuring Product Quality

CNC block guards are components for your engine’s safety. So, you can never compromise the reliability of the product’s quality. Ensure the manufacturer highly prioritizes to ensure the standard quality of every product.

Follow Manufacturer Certifications

Follow the certifications of the manufacturer and the products. If you see the certificates are in International compliance, you can proceed ahead.

Material Selection And Quality Of Finishing

The best CNC manufacturers maintain stocks of different types of materials. Based on requirements, they choose the best material for your product with variable qualities of surface finishing. For a CNC block guard, choose the manufacturer that uses aluminum as material and performs the best surface finishing for wearing protection.

Quality Verification Tests

The best manufacturers of CNC block guards always ensure to maintain quality verification steps on their products. In this regard, choose the manufacturer who regularly performs a hardness test, Magnaflux test, ultrasonic test, and other relevant tests to ensure the product’s reliability.

Experienced Manufacturer

Choose the manufacturer who has been in the industry for a long time. These manufacturers are experienced. Moreover, they keep their tracks updated with the latest features and technology.figure 2 what car parts can you make with cnc

Guidance for Custom CNC Block Guard From Manufacturers

When custom ordering a CNC block guard from manufacturers, start by clearly specifying your needs and conducting extensive research to locate reliable companies that have advanced CNC machining capabilities. Ask for accurate price quotations, discuss design parameters and find out whether the supplier adheres to strict quality assurance systems. Costs, lead times and request samples for evaluation. Keep lines of communication open during the production process and conclude contract terms, also perform a quality inspection after the receipt of custom block guards. Giving feedback and developing a friendly working environment is necessary for future possible collaboration.


CNC block guards plays a key role in the safety of the engine more so under harsh conditions. Manufactured to perfection with the use of CNC milling, these units strengthen the top wall of the engine thus preventing crack formation. Durability is improved by using aluminium alloys, anodizing or powder coating. They do not only protect engines but also increase power and efficiency by controlling heat. When you want custom CNC block guards, investigate manufactures, emphasize quality considerations and make certain communication is clear. In summary, the CNC block guards are essential for engine protection and operation efficiency which makes it a good choice for harsh conditions.

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