1. What is the Exhaust Diameter Calculation?

The exhaust diameter calculation determines the optimal pipe size for an engine's exhaust system based on displacement, RPM, and desired exhaust gas velocity. Proper sizing is critical for engine performance and efficiency.

2. How Does the Calculator Work?

The calculator uses the exhaust diameter formula:

Where:

• \( d \) — Exhaust diameter (inches)
• \( displacement \) — Engine displacement (cubic inches)
• \( RPM \) — Engine revolutions per minute
• \( velocity \) — Exhaust gas velocity (feet per second)

Explanation: The equation balances exhaust flow requirements with velocity to minimize backpressure while maintaining adequate scavenging.

3. Importance of Proper Exhaust Diameter

Details: Correct exhaust diameter improves engine efficiency, power output, and fuel economy while reducing backpressure and excessive noise.

4. Using the Calculator

Tips: Enter engine displacement in cubic inches, typical operating RPM, and desired exhaust gas velocity (typically 200-300 ft/s for street vehicles).

5. Frequently Asked Questions (FAQ)

Q1: What's a typical exhaust gas velocity range?
A: Street vehicles: 200-300 ft/s, performance applications: 300-400 ft/s, race cars: up to 500 ft/s.

Q2: How does diameter affect performance?
A: Too small creates excessive backpressure, too large reduces exhaust velocity and scavenging effect.

Q3: Should I use this for header primary tubes?
A: This calculates collector/muffler inlet size. Header primaries require different calculations.

Q4: Does this work for turbocharged engines?
A: Turbo engines require different calculations due to the turbine's effect on exhaust flow.

Q5: What about dual exhaust systems?
A: For dual exhaust, calculate total flow then divide by 2 for each pipe's diameter.