Discover what a custom catback exhaust is, how it differs from stock systems, and whether it adds real power or just noise. Learn about materials, installation pitfalls, and acoustic tuning.
For a 400hp engine, the right exhaust size is usually 3 to 3.5 inches. Too small restricts flow; too big kills torque. Learn what works for turbo 4-cylinders, V6s, and V8s-and avoid common mistakes.