What do you need to get 400hp out of a 1984 351w?

To achieve 400 horsepower from a 1984 Ford 351 Windsor (351W), you'll need to upgrade several key components. Focus on a high-performance intake manifold, a quality aftermarket carburetor or fuel injection system, and a set of high-flow cylinder heads. Additionally, a performance camshaft designed for increased lift and duration, along with a proper exhaust system, will help maximize airflow and power output. Finally, ensuring proper tuning and supporting modifications, such as a stronger ignition system and upgraded fuel delivery, will be essential for reliability and performance.