The Pontiac 400 cubic inch engine is one of the most underappreciated American V8s of the muscle car era. It was available in multiple states of tune, from the mild 265-horsepower version in the base GTO to the Ram Air IV at 370 horsepower.

The Ram Air IV is the ultimate expression: round-port cylinder heads, aggressive camshaft, high-compression pistons, and a free-breathing exhaust. It was designed specifically for the Trans-Am racing program and adapted for street use.

The Pontiac 400 was produced exclusively at Pontiac — not a corporate engine shared across divisions — and Pontiac engineers had a specific philosophy about how an engine should perform. The result was an engine with excellent torque characteristics that pulled hard from low rpm, quite different from the high-revving Chevrolet small block approach.