For 1966, the Pontiac GTO became its own standalone model rather than an option package, marking a major milestone in its evolution. A dramatic “Coke bottle” body redesign gave the car a wider, more aggressive stance, while the 389 V8 continued to deliver impressive horsepower figures up to 360 with Tri-Power. New styling details such as louvered taillights and a revised interior added refinement to the performance formula. With record-breaking sales, the 1966 GTO is often considered one of the most successful and recognizable muscle cars of the decade.