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SBC Compression Height Calculator

Compression Height Formula:

\[ CH = BD - (SH + PL) \]

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1. What is a Compression Height Calculator?

Definition: This calculator determines the compression height (CH) of an engine based on block deck height (BD), stroke height (SH), and piston length (PL).

Purpose: It helps engine builders and automotive enthusiasts calculate the critical compression height measurement for proper engine assembly.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ CH = BD - (SH + PL) \]

Where:

Explanation: The stroke height and piston length are subtracted from the block deck height to determine the compression height.

3. Importance of Compression Height

Details: Proper compression height calculation ensures correct piston positioning, proper compression ratio, and prevents piston-to-head contact.

4. Using the Calculator

Tips: Enter the block deck height, stroke height, and piston length in millimeters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is block deck height?
A: The vertical distance from the crankshaft centerline to the deck surface of the engine block.

Q2: How is stroke height determined?
A: Stroke height is half of the engine's stroke (crank throw × 2).

Q3: What affects compression height?
A: Rod length, crank stroke, and piston design all influence the required compression height.

Q4: Why is compression height critical?
A: It determines piston position at top dead center (TDC), affecting compression ratio and valve clearance.

Q5: What if my calculated CH is negative?
A: This indicates an incompatible combination of components that would cause piston-to-head contact.

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