How To Degree A Cam

How to Degree a Cam: A Comprehensive Guide

Degreing a cam is a crucial step in engine building, ensuring proper valve timing and optimal engine performance. This process involves precisely aligning the camshaft's lobes with the crankshaft's position. Getting it wrong can lead to poor engine running, reduced power, and even engine damage. This guide will walk you through the process, covering everything from the necessary tools to troubleshooting common issues.

Understanding Cam Degreeing

Before diving into the procedure, let's clarify what cam degreing entails. It's the process of precisely measuring and adjusting the camshaft's timing relative to the crankshaft. This ensures your valves open and close at the optimal points in the engine's cycle, maximizing power and efficiency. Factory-installed cams are usually pre-degreed, but aftermarket cams require this careful adjustment.

Why Degree a Cam?

• Optimal Valve Timing: Achieving precise valve timing is essential for maximizing engine performance. An incorrectly degreed cam can lead to significant power loss.
• Aftermarket Camshafts: Aftermarket camshafts often require degreing because they have different lobe profiles and timing specifications compared to stock cams.
• Engine Modifications: Significant engine modifications, such as changes to the cylinder head or intake manifold, can necessitate cam degreing to maintain optimal performance.
• Troubleshooting Performance Issues: If your engine isn't performing as expected, incorrect cam timing might be the culprit. Degreing can help diagnose and resolve such issues.

Tools and Equipment Needed

Before you begin, ensure you have the following tools and equipment:

• Degree Wheel: This is the cornerstone of the process. A degree wheel accurately measures crankshaft rotation.
• Dial Indicator: Used to measure valve lift and ensure precise cam lobe alignment.
• Timing Light: Helps verify the accuracy of your timing marks.
• Wrench Set: For removing and installing components.
• Socket Set: For accessing various fasteners.
• Torque Wrench: Crucial for tightening components to the manufacturer's specifications.
• Cam Degreeing Kit: While not strictly necessary for all applications, these kits often include useful tools and instructions, simplifying the process.
• Shop Manual: Consult your engine's shop manual for specific instructions, torque specifications, and timing marks. This is crucial for a successful outcome.

Step-by-Step Guide to Degreing a Cam

This is a general overview. Always refer to your engine's specific shop manual for detailed instructions tailored to your engine. Improper procedure can cause serious engine damage.

1. Preparation: Remove the valve covers and ensure the engine is properly aligned at top dead center (TDC) on the compression stroke of the number one cylinder. Double-check this several times!
2. Install Degree Wheel: Securely mount the degree wheel to the crankshaft, ensuring accurate alignment.
3. Install Dial Indicator: Position the dial indicator to accurately measure valve lift. This is often done using a magnetic base attached to the cylinder head.
4. Zero the Dial Indicator: Zero the dial indicator at the point of minimum valve lift.
5. Rotate Crankshaft: Slowly rotate the crankshaft, noting the degree wheel readings and the corresponding valve lift.
6. Measure Valve Lift: Carefully record valve lift measurements at various crankshaft positions, specifically focusing on the intake and exhaust lobes.
7. Adjust Cam Timing (if necessary): Based on your measurements and the camshaft's specifications, you may need to adjust the camshaft's position to achieve the desired valve timing. This often involves loosening and repositioning the camshaft gear.
8. Re-measure and Verify: After making any adjustments, re-measure valve lift to ensure accuracy. Repeat this process until the valve lift matches the camshaft's specifications.
9. Reassemble: Once you're satisfied with the timing, carefully reassemble the engine. Remember to torque all fasteners to the manufacturer's specifications.
10. Verify Timing: Use a timing light to verify the accuracy of your cam timing before starting the engine.

Troubleshooting Common Issues

• Inaccurate Degree Wheel Alignment: Ensure the degree wheel is properly aligned with the crankshaft before proceeding.
• Dial Indicator Placement: Incorrect dial indicator placement can lead to inaccurate measurements. Double-check this carefully.
• Misinterpretation of Specifications: Always refer to the camshaft manufacturer's specifications and your engine's shop manual for precise instructions.
• Incorrect Torque: Tightening bolts to the incorrect torque can damage engine components.

Disclaimer: Degreing a cam is a complex procedure that requires mechanical aptitude and attention to detail. If you are not comfortable performing this task, it's best to consult a qualified professional. Incorrectly degreed cams can lead to serious engine damage. This guide is for informational purposes only and does not constitute professional advice.