Ford Mustang Boss 351The 1971 Boss 351 was Ford's way of giving the legendary Boss Mustang lineup a proper send-off, and what a farewell it was. The model was powered by the 351 Cleveland V8 engine, which Ford specifically modified for high performance. We're talking about a solid-lifter camshaft, an aluminum intake manifold, a specially tuned four-barrel carburetor, and a unique dual-point distributor. All of this helped the Boss 351 produce 330 horsepower and 370 lb-ft of torque, making it one of the most powerful Mustangs of its time.It could go from 0 to 60 mph in just 5.8 seconds and complete a quarter-mile run in 14.1 seconds. Ford paired the engine with a close-ratio four-speed manual transmission, allowing drivers to make the most of its high-revving powerband. To handle all that speed, Ford engineers gave the Boss 351 a competition suspension setup. It came with staggered rear shocks, where one shock faced forward and the other backward, to reduce wheel hop and improve traction under hard acceleration. The car also featured power front disc brakes and a quick-ratio steering system, which made it surprisingly agile for a muscle car of its size.In terms of looks, the Boss 351 had a NACA hood scoop, bold black stripes on the hood, and subtle "Boss 351" to let people know this wasn't a regular Mustang. The chrome bumpers and trim added a touch of style. However, its wide roof pillars and seat positioning made it harder for drivers to get a clear view out the rear window.Nonetheless, the Boss 351 remains a special part of Mustang's history. While future Mustangs would eventually surpass its performance, it really was just the most refined version of Ford's first-generation high-performance Mustangs until the Boss name was revived decades later.Buick GSX Stage 1Buick wasn't known for making muscle cars, but the 1970 GSX Stage 1 changed that. Buick had a reputation for building comfortable, refined cars, but with this model, they set out to prove they could do high performance just as well as anyone else.Unlike many muscle cars that focused only on speed, the GSX Stage 1 was designed to deliver both power and comfort. Under the hood was a massive 455 cubic-inch V8 engine that produced 360 horsepower and an astonishing 510 lb-ft of torque— a record that no other American car could break until 2003. Buick gave the Stage 1 package extra performance upgrades, including larger valves, a stronger camshaft, and a recalibrated carburetor, making it one of the fastest muscle cars of its time. It could run a quarter-mile in just 13.4 seconds while still offering a smooth and refined ride.Buick also tuned the suspension to balance performance and comfort, adding heavy-duty springs, special shock absorbers, and a rear stabilizer bar. The GSX Stage 1 was just as fast as it was stylish. It came in two colors: Saturn Yellow or Apollo White, with bold black stripes running across the body. It also came with a functional hood-mounted tachometer and special GSX badging to make sure everyone knew this wasn't just another Buick.Inside, the car had bucket seats, a floor shifter, and a full set of gauges, including a vacuum gauge built into the hood-mounted tachometer. Buick only built 678 units, making it one of the rarest muscle cars of its era. Each one came with detailed documentation and a special GSX warranty book.