Installing SBC Cam Bearings: A Comprehensive Guide

Installing cam bearings is a crucial step in building a high-performance Small Block Chevrolet (SBC) engine. These bearings support the camshaft and ensure its proper alignment and lubrication. Incorrect installation can lead to severe engine damage. This article provides a comprehensive guide to installing SBC cam bearings, covering everything from preparation to final torque specifications.

Preparation

Before installing cam bearings, it is essential to prepare the engine block and camshaft.

1. Clean the Engine Block: Remove all dirt, grease, and debris from the camshaft bores using a solvent and a brush.
2. Inspect the Camshaft Bores: Check the camshaft bores for any damage or wear. If necessary, have the bores honed to the correct size.

Types of SBC Cam Bearings

There are two main types of SBC cam bearings:

1. Press-In Bearings: These bearings are pressed into the camshaft bores using a special tool.
2. Drop-In Bearings: These bearings simply drop into the camshaft bores and are secured with a retaining pin.

Step-by-Step Guide to Installing SBC Cam Bearings

Materials:

• Cam bearings
• Cam bearing installation tool (for press-in bearings)
• Retaining pins (for drop-in bearings)
• Hydraulic press (for press-in bearings)
• Torque wrench
• Engine oil or assembly lube
• Rags

Step 1: Select the Correct Bearings

Choose the correct cam bearings for your SBC engine based on the camshaft size and journal diameter. Refer to the table below for common camshaft sizes and corresponding bearing sizes.

Step 2: Lubricate the Bearings

Apply a thin layer of engine oil or assembly lube to the outside surface of the cam bearings. This will aid in installation and reduce friction during camshaft operation.

Step 3: Install the Bearings

For Press-In Bearings:

1. Align the bearing with the camshaft bore.
2. Place the cam bearing installation tool over the bearing.
3. Use a hydraulic press to gradually press the bearing into the bore until it is fully seated.

For Drop-In Bearings:

1. Drop the bearing into the camshaft bore.
2. Install the retaining pin to secure the bearing.

Step 4: Inspect the Bearings

Once all the cam bearings are installed, inspect them to ensure they are properly seated and there is no damage.

Step 5: Torque the Cam Bolts

Install the camshaft into the cam bearings and torque the cam bolts according to the manufacturer's specifications. Refer to the table below for typical cam bolt torque specifications.

Tips and Tricks:

• Use a dial indicator to ensure the camshaft is running true after installation.
• Apply a thread sealant to the cam bolts to prevent oil leaks.
• Let the engine oil circulate through the cam bearings before starting the engine.

Common Mistakes to Avoid

• Installing the Bearings Upside Down: This can lead to oil starvation and premature camshaft failure.
• Overtightening the Cam Bolts: This can damage the camshaft and bearings.
• Not Aligning the Bearings Properly: This can create excessive friction and wear on the camshaft and bearings.

Conclusion

Installing cam bearings is a relatively straightforward process, but it requires care and attention to detail. By following the steps outlined in this article, you can ensure that your SBC engine has properly installed cam bearings that will provide years of reliable service.

Remember, it is always advisable to consult with an experienced mechanic if you are not comfortable performing this task on your own.