Stroking A 327 Engine: Is It Possible And Safe?

The 327 Chevy engine has a small 3.250-inch stroke, while the 350 has a longer 3.480-inch stroke. The 327 was a popular Corvette engine, and the 350 was not available until 1967. The 350 only became popular in 1968 when it was introduced in some car models. The 327 has a reputation for being a more powerful engine than the 350, but this is a misconception. The 350 has more torque and will make more horsepower with the same modifications. However, the 327 can rev higher due to its shorter stroke and less reciprocating mass.

Stroking a 327 engine to a 350

To convert a 327 to a 350, the mains on the 350 crank need to be turned down to small journal size. The flange between the rear main journal and the rear main seal will also need to be slightly reduced. It is also recommended to use the longer 350 bolts for the main caps.

While it is possible to convert a 327 to a 350, it is not a straightforward process and there are other factors to consider such as the availability of parts and the cost of the conversion. It may be more cost-effective to simply purchase a 350 engine or consider a different engine build altogether.

Stroking a 327 engine to a 383

To stroke a 327 engine to a 383, you will need to start with a 327 block and a 400 crank. The 400 crank will need to be cut down to 350 size (2.65 inches down to 2.45 inches). Additionally, the 327 block will need to be line bored/honed to 350 size, and new notches will need to be cut into the block for the 350 bearings. The groove in the rear cap of the 327 block will also need to be turned down slightly to accommodate the 350 crank. Finally, the bottom of the cylinders will need to be cleared for rod bolts when installing the 400 crank.

When choosing the components for your stroker engine, it is important to consider your intended use. If you are building a high-performance engine, you may want to invest in aftermarket aluminium cylinder heads, which offer improved airflow and efficiency over the factory iron heads. For a more mild street build, the factory iron heads can be modified and used with good results. It is also important to choose the correct camshaft for your intended use, as well as the correct piston deck height and compression ratio to match your cylinder heads.

Another option to consider is stroking the 327 engine to a 355, which can be achieved by boring the 327 block to 4.030 inches and installing a 350 crank with the main journals turned down to 350 size. This option is less expensive than stroking to a 383 and may be more suitable for a mild street build.

Stroking a 327 engine to a 355

To achieve this, you would need to replace the crankshaft with one that has a longer stroke, such as a 350 crank with a 3.48" stroke or a custom-modified crank with an even longer stroke. Additionally, you would need to ensure compatibility by checking the journal sizes and making any necessary modifications, such as machining or grinding, to ensure a proper fit. It is also important to consider the piston and rod combination, as these components need to be compatible with the longer stroke and each other.

When stroking a 327 engine to a 355, it is essential to choose high-quality parts and perform precise measurements and machining. The piston deck height, cylinder head chamber volume, and quench clearance are critical factors in achieving efficient combustion and maximizing performance. It may be necessary to clearance the block to accommodate the longer stroke and ensure there is no interference with other components.

While stroking a 327 engine to a 355 can be a complex and technical process, it can result in increased horsepower and torque output. It is important to carefully plan and execute the modifications to ensure a reliable and high-performing engine.

Stroking a 327 engine to a 400

To stroke a 327 engine to a 400, you have a few options:

• Using a 400 Crankshaft: You can install a 400 crankshaft, which will increase the stroke and result in a displacement of approximately 383 cubic inches. This option may require some clearancing of the block and cylinder boring to accommodate the longer stroke.
• Using a 350 Crankshaft: Another option is to use a 350 crankshaft, which will give you a 350 cubic inch displacement. This is a more cost-effective option and may be a better choice if you are on a budget.
• Using a 307 Crankshaft: If you want to keep costs down, consider using a 307 crankshaft. This will require balancing the crankshaft to accommodate heavier pistons due to the larger bore.
• Using a 350 or 400 Crank and Rods: You can also stroke the 327 to a 383 by using a 350 or 400 crank and rods. This will require clearancing the block and choosing the appropriate piston to match the rod length.

It is important to note that the process of stroking a 327 engine to a 400 may vary depending on the specific engine configuration and the machine work required. It is always recommended to consult with a professional or a machine shop to ensure the work is done correctly and safely.

Additionally, when stroking an engine, it is crucial to consider the compression ratio, cylinder head, camshaft, and valve train components to ensure they complement the increased displacement and desired power output.

Stroking a 327 engine to a 302

However, if you are determined to stroke a 327 engine to a 302, there are a few things you should keep in mind. First, you will need to find the right parts. This may include a custom crank, custom rods, and custom pistons. You can try to find these parts from specialty suppliers, but they may be expensive and hard to come by. Another option is to use a 283 crank with 327 pistons, but you will need to make sure that the pistons fit the block properly.

It's also important to consider the deck height of the block. You may need to remove some material from the top of the pistons to get the correct deck height. Additionally, the rod angle on the small Fords is already steep, so you will need to pay extra attention to cylinder/piston integrity for decent engine life.

Finally, keep in mind that stroking an engine can be a complex and costly process. It may be more cost-effective to simply buy a bigger engine, such as a 350 or a 383, rather than trying to stroke a 327 to a 302.

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