1. What is Compression Height?

Compression Height (CH) is the distance from the centerline of the wrist pin to the top of the piston. It's a critical measurement in engine building that affects piston-to-head clearance and compression ratio.

2. How Does the Calculator Work?

The calculator uses the Wallace and Smith formula:

Where:

• \( Block \) — Block height (deck surface to crankshaft centerline)
• \( Rod \) — Connecting rod length (center-to-center)
• \( Stroke \) — Crankshaft stroke length
• \( Deck\ Clearance \) — Distance piston is below deck at TDC

Explanation: The formula accounts for all components that affect the piston's position relative to the deck at top dead center (TDC).

3. Importance of Compression Height

Details: Proper compression height ensures correct piston placement for optimal combustion chamber volume, valve clearance, and overall engine performance.

4. Using the Calculator

Tips: Enter all measurements in inches. Block height, rod length, and stroke must be positive values. Deck clearance can be zero if piston is flush with deck at TDC.

5. Frequently Asked Questions (FAQ)

Q1: Why is compression height important?
A: It determines piston placement which affects compression ratio, quench area, and valve-to-piston clearance.

Q2: What's a typical compression height range?
A: Varies by application but typically between 1.0-1.8 inches for most V8 engines.

Q3: How does this relate to compression ratio?
A: CH affects the combustion chamber volume at TDC, which is a key factor in compression ratio calculations.

Q4: What if my calculated CH is negative?
A: This indicates the piston would extend above the deck at TDC, which is generally not feasible.

Q5: How precise should measurements be?
A: For performance engines, measurements should be to the nearest 0.001 inch for accuracy.