Exhaust Diameter Calculator
Size exhaust components for optimal flow based on engine output and configuration.
Exhaust Sizing Chart (Single Pipe)
| HP Range | Single | Dual (each) |
|---|---|---|
| 100-200 | 2.00" | 1.75" |
| 200-300 | 2.25" | 2.00" |
| 300-400 | 2.50" | 2.25" |
| 400-500 | 3.00" | 2.50" |
| 500-600 | 3.50" | 2.75"-3.00" |
| 600+ | 4.00"+ | 3.00"-3.50" |
Exhaust Sizing Principles
Flow Calculations
Exhaust pipe diameter is calculated using:
D = sqrt(HP / 13.5) for single
D = sqrt(HP / 27) for each dual pipe
Boosted applications require 10-15% larger sizing. Mandrel bends maintain better flow than crush bends.
Component Sizing
- Primaries: sized to port size and RPM range
- Collectors: merge area equals primary area sum
- Cats: high-flow units sized to pipe diameter
- Mufflers: match inlet to pipe, consider flow rating
- Bigger is not always better - velocity matters