Stroking Secrets: Transforming A 289 To A 347

There is much debate about whether it is possible to stroke a 289 to a 347. Some people claim that the 289 block has shorter cylinders than the 302, which would make it impossible to stroke the 289 to a 347. However, others claim that they have measured the cylinders of both engines and found no significant difference in length, making it safe to perform the stroke. While it seems that it is technically possible to stroke a 289 to a 347, there are other factors to consider, such as the strength of the block and the type of heads used.

It is possible to stroke a 289 to a 347, but the 289 block has a shorter cylinder skirt, which means less piston support at the bottom of the stroke

It is possible to stroke a 289 to a 347, but there are some important considerations to keep in mind. Firstly, the 289 block has a shorter cylinder skirt, which can result in less piston support at the bottom of the stroke. This is because the cylinder skirt is the part that extends towards the crankcase, and the shorter skirt on the 289 block can affect the stability of the piston.

Due to the shorter cylinder skirt, some builders prefer not to use a 289 block for stroking to a 347, as it may not be able to handle high revolutions or boost. However, it is important to note that several people have successfully built a 347 using a 289 block, as long as the engine is not revved too high.

When considering a 347 stroker kit, it is important to ensure compatibility with the 289 block. The cylinder bore depth and stroke length are critical factors, and it is recommended to choose a kit with longer connecting rods to maintain piston stability. Additionally, the type of crankshaft and the number of pieces in the rear main seal should be considered, as modifications may be required for newer cranks in older blocks.

To ensure the longevity of the engine, it is crucial to address the shorter cylinder skirt issue. One possible solution is to add a main girdle, which provides additional support to the main caps and can help prevent movement. Another option is to upgrade to a four-bolt '69-71 Boss block, which offers stronger block integrity compared to the early 6-bolt blocks.

In summary, while it is possible to stroke a 289 to a 347, the shorter cylinder skirt of the 289 block can impact piston support and engine performance. Proper modifications, careful kit selection, and additional support measures can help mitigate these issues and ensure a reliable 347 stroker engine.

Some builders prefer not to use a 289 block for stroking to 347, but others have done it without issues

Some builders prefer not to use a 289 block for stroking to 347 because the 289 block has a shorter cylinder skirt, which means the piston has less support at the bottom of the stroke. This can lead to main cap movement at high RPMs.

However, others have successfully stroked a 289 to a 347 without issues. Some have even taken their engines to 7,000 RPMs without adding a girdle. It is important to note that the cylinder length of the 289 and 302 blocks is the same at 5 1/8", contrary to the belief that the 302 has longer cylinders.

When considering a 347 stroker kit for a 289 block, it is crucial to distinguish between the early 289/302 non-roller blocks and the later roller blocks. The early non-roller blocks have shorter bore skirts compared to the later roller blocks. Additionally, the 2-piece rear seal 302 blocks are completely interchangeable with the 289 blocks.

It is recommended to add a main girdle for extra support and to prevent main cap movement, especially if you plan on revving the engine to high RPMs.

In conclusion, while some builders prefer not to use a 289 block for stroking to 347 due to concerns over piston support and main cap movement, others have successfully done so without encountering any issues. It is important to consider the specific characteristics of your block, such as cylinder length and type of block, when making this modification.

The 289 and 302 blocks have the same bore length, so the 289 block can accommodate the longer stroke of the 347 crank

The 289 engine, with its 4.030-inch bores, can be stroked to 3.400 inches of piston travel to create a 347ci engine. This increase in displacement allows for more fuel and air per charge, resulting in greater power. The longer connecting rod also increases piston dwell time, contributing to the power gain.

While some builders prefer not to use the 289 block for stroking due to its shorter cylinder skirt, which provides less piston support at the bottom of the stroke, many people have successfully built 347s with 289 blocks. It is recommended to avoid high revolutions per minute (RPM) or boost with this setup for better reliability.

When considering a 347 stroker kit for a 289 block, it is important to note that the cylinder bores and crank specifications must be taken into account. The 289 block has a shorter cylinder bore than the 302, and the 347 crank has a longer stroke. However, the difference in cylinder depth between the 289 and 302 blocks is minimal, and some builders have reported successful combinations of the 289 block with the 347 crank.

To ensure the compatibility and performance of the 347 stroker in a 289 block, it is essential to consult with experienced builders and follow their recommendations for specific parts, clearances, and modifications. Additionally, proper bearing installation and dynamic balancing of rotating and reciprocating parts are crucial for the durability and smoothness of the engine.

A 347 stroker kit can be used with a 289 block, but the cylinder bores are shorter, which can affect piston stability

A 347 stroker kit can be used with a 289 block engine, but there are some important considerations to keep in mind. The cylinder bores in the 289 block are shorter compared to other blocks, which can potentially affect piston stability and engine performance.

The 289 block engines were produced with slightly shorter cylinder walls or skirts. This means that when the engine is stroked to a larger capacity, such as 331 or 347 cubic inches, the piston may not have as much support at the bottom of its stroke. This can lead to stability issues and potential engine damage if not addressed properly.

However, it is important to note that many people have successfully built 347 stroker engines using 289 blocks. The key to a reliable setup is to avoid high revolutions per minute (RPM) and boost. Keeping the engine within a safe operating range can help mitigate the risks associated with the shorter cylinder bores. Additionally, some builders have reported using a main girdle to enhance piston stability.

When considering a 347 stroker kit for a 289 block, it is crucial to consult with experienced builders and follow their recommendations. While it is possible to achieve satisfactory results, careful planning and attention to detail are necessary to ensure the engine's reliability and longevity.

Furthermore, when building a 347 stroker engine, other factors come into play, such as piston type, rod ratio, and block modifications. It is essential to select the right components and make any necessary adjustments to the block to accommodate the increased stroke and ensure optimal performance and durability.

In summary, while it is possible to use a 347 stroker kit with a 289 block, the shorter cylinder bores of the 289 block can affect piston stability. Careful consideration, proper component selection, and adherence to safe operating ranges are key to a successful and reliable 347 stroker engine build.

When building a 347 engine, it's important to consider piston type, rod ratio, stroke, and block modifications for optimal performance and durability

The 347 engine is a popular choice for those seeking more power and torque from their vehicle. To build a 347 engine, you essentially take a 289 or 302 engine and increase the piston travel to 3.400 inches. This increase in stroke results in a larger displacement, allowing more fuel and air per charge, which ultimately leads to a boost in power.

When building a 347 engine, here are the key factors to consider:

Piston Type:

The type of piston you choose will depend on your intended usage and budget. For a budget build, hypereutectic pistons are a common choice, as they offer a good balance between performance and cost. For high-performance applications, forged pistons are recommended. Forged pistons, such as those from Wiseco, JE, Arias, or Trick Flow, offer superior strength and durability, making them ideal for high-rpm and forced induction setups.

Rod Ratio:

The rod ratio, or connecting rod length, plays a crucial role in the performance of a 347 engine. A longer connecting rod results in greater piston dwell time at the top and bottom of the stroke, which yields more power. However, longer rods can also lead to increased wear on the cylinder wall, especially in high-mileage engines. It's important to select a rod ratio that aligns with your intended usage and to ensure proper clearance during assembly.

Stroke:

The stroke of a 347 engine is typically increased to 3.400 inches, up from the 289's original stroke of around 3.000 inches. This longer stroke contributes to the increased displacement and power output of the 347 engine. However, it's important to note that the longer stroke may require block clearancing and can impact the counterweight and oil control. Some aftermarket manufacturers, like Eagle, offer solutions to address these issues.

Block Modifications:

When building a 347 engine, modifications to the engine block are often necessary. The cylinder bores may need to be notched for proper clearance, especially on Ford 289/302 blocks. It's crucial to carefully measure and mark the areas that require grinding or notching to ensure a precise fit for the larger pistons. Additionally, it's important to thoroughly clean the block after any machining work to remove any metal shavings or residue that could contaminate the engine oil.

In summary, building a 347 engine requires careful consideration of piston type, rod ratio, stroke, and block modifications. By selecting the right components and making the necessary adjustments, you can achieve optimal performance and durability from your 347 engine.

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