38. Mercury Cougar XR-7 GT
They built the Mercury Cougar on the Mustang platform but stretched it a couple of inches to add comfort and achieve a better ride quality. Also, the Mercury Cougar was available with V8 engines only, while they reserved the small six-cylinder units for entry-level Mustangs. Some say the Cougar was just a luxury Mustang. But in reality, it was an independent model and a successful car in its own right. Until 1969 they only offered coupes and not convertibles.
However, it was the ultimate version that perfectly combined muscle car power and luxury in the mighty Cougar XR-7. This model had the 390 V8 engine with 320 HP. Also, buyers could opt for the GT package with a beefed-up suspension, stronger brakes, and updated steering. The XR-7 was quite a popular model, so they built over 27,000 in 1967. But only a little over 2,600 came with the GT package, making it a rare and desirable model.