1. What is Valve Lift?

Valve lift refers to the maximum distance the valve moves away from its seat during the camshaft's rotation. It's a critical factor in engine performance, affecting airflow into and out of the combustion chamber.

2. How Does the Calculator Work?

The calculator uses the valve lift formula:

Where:

• \( Valve\ Lift \) — Maximum valve opening distance (mm)
• \( Cam\ Lift \) — Maximum lobe height on camshaft (mm)
• \( Rocker\ Ratio \) — Mechanical advantage of rocker arm (dimensionless)

Explanation: The rocker arm multiplies the cam lobe's movement to produce greater valve lift than the cam lobe alone could provide.

3. Importance of Valve Lift Calculation

Details: Proper valve lift calculation is essential for engine tuning, ensuring optimal airflow while preventing valve-to-piston contact. It affects horsepower, torque, and engine efficiency.

4. Using the Calculator

Tips: Enter cam lift in millimeters and rocker ratio (typically between 1.5:1 to 1.8:1 for most trucks). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical rocker ratio for trucks?
A: Most stock truck engines use ratios between 1.5:1 to 1.7:1, while performance builds may use 1.8:1 or higher.

Q2: How does valve lift affect performance?
A: Increased lift generally improves airflow and power, but excessive lift can cause valve float or piston contact.

Q3: Can I change rocker ratio without changing cams?
A: Yes, but this affects valve timing and spring pressure requirements. Professional tuning is recommended.

Q4: What's the maximum safe valve lift?
A: This depends on your specific engine's piston-to-valve clearance and valve spring capabilities.

Q5: Does valve lift affect fuel economy?
A: Yes, increased lift can improve efficiency at higher RPMs but may reduce low-RPM torque in some cases.