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🔧 Exhaust Diameter Calculator
Calculate exhaust pipe diameter, flow capacity, and backpressure for optimal engine performance
📐 Exhaust Diameter Formulas
D = √(4 × A / π)
A = (Engine Displacement × RPM × VE) / (CFM × 1728)
CFM = (CID × RPM × VE) / 3456
Velocity = CFM / (A × 60)
D = diameter, A = cross-sectional area, CFM = cubic feet per minute, VE = volumetric efficiency, CID = cubic inch displacement
💡 Tips
- Larger diameter reduces backpressure but may hurt low-end torque
- Optimal velocity is 200-300 ft/s for most applications
- Consider engine displacement and RPM range
- Dual exhaust systems need smaller individual pipes
- Turbocharged engines need larger diameter pipes
- Balance flow capacity with exhaust velocity