Find the perfect exhaust size for your 350 hp engine. Learn how pipe diameter affects torque, horsepower, and backpressure for both NA and turbo builds.
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.