10 classic American muscle cars
By Daniel Bukszpan 
A muscle car might be defined as simply a high-performance two-door car made in the U.S., but to its fans it's much more than that. The muscle car is the basis for an entire subset of car fans, and movies such as "Bullitt" that have featured them prominently have helped create a lasting high-speed subculture.
Karl Brauer, editor-in-chief of the online car review aggregator Total Car Score, is a self-described muscle car fanatic who characterizes these vehicles as his "primary passion." He provided CNBC.com with his list of 10 classic American muscle cars and some eye-popping estimates of their current market value.
"Vintage car collectors consider these must-have muscle cars, which is undoubtedly driving up the prices," Brauer said. He said that prices are likely to keep climbing, so if there's any time to buy a muscle car, it's now.
"The 1969-1970 Boss 429 Mustang, for instance, has skyrocketed in value over the past two years," he said. "If you're looking to buy you should act sooner rather than later. These vehicles will all likely cost more six to 12 months from now.
Read ahead to see the list of 10 classic American muscle cars.
1970 Oldsmobile 442 W-30
Oldsmobile is not a name commonly associated with the muscle car era. Nevertheless, this company still made its contributions back then, which included the 1970 Oldsmobile 442 W-30.
"At the peak of the muscle car era, Oldsmobile offered a 455 cubic inch V-8 engine in the brand's 442 muscle car," Brauer said. "When equipped with the W-30 option the 1970 Oldsmobile 442 was rated at 370 horsepower and 500 pound-feet of torque, often while sporting such luxuries as air conditioning and power windows." Its current market value is $35,000.
1974 Pontiac Firebird Trans Am SD455
According to Brauer and to many fans, the muscle car's golden age came to an end in 1971. However, a small but determined group of engineers at Pontiac remained undeterred, and created an evolved Ram Air IV engine, which turned up under the hood of the 1974 Firebird.
Despite its late vintage, Brauer called this Trans Am "a fully capable muscle car." The current market value of the 1974 Pontiac Firebird Trans Am SD455 is $75,000.
1970 Buick GSX Stage 1
"Buick was a performance player back in the muscle car days, with 455 cubic inch V-8s offered in the company's Gran Sport (GS) models," Brauer said. "The top dog was the 1970 Buick GSX with the 455 Stage 1 engine rated at 370 horsepower and 510 pound-feet of torque."
Only 400 of these GSXs were produced, so its relatively limited production run has kept it somewhat valuable among collectors and enthusiasts. Its current market value is $75,000.
1970 Chevrolet Chevelle SS 454 LS6
The 1970 Chevrolet Chevelle SS 454 LS6 was a beast, plain and simple. The 450 horsepower assigned to this Chevelle V-8 is the highest power rating ever given to a car from the original muscle car era, according to Brauer.
The high rating, however, was an understatement. "Even this rating was below the engine's actual horsepower, which was likely somewhere between 470 and 500 horsepower," he said. This Chevelle's current market value is $75,000.
1970 Pontiac GTO Judge Ram Air IV
"Pontiac's GTO started the official muscle car era in 1964," Brauer said. "By 1970 the competition on the street, and in the showrooms, required every automaker to step up their efforts."
Even Pontiac itself had to raise its game, which it did by introducing the GTO Judge. According to Brauer, it's "powered by the Ram Air IV engine, a 400 cubic inch V-8 with special high-flow heads and unique exhaust manifolds." Its current market value is $80,000.
1968 Ford Mustang GT500KR
"Carroll Shelby has a history of hot-rodding Mustangs that started in 1965," Brauer said of the late Ford Motor designer. Production of his Mustangs switched from his own shop to the Ford facilities in 1968, when the GT500KR was built.
Brauer called this muscle car "one of the most attractive and capable Shelby Mustangs ever created." He added that only 933 coupes were built, along with 318 convertibles. Its current market value is $130,000.
1969 Ford Boss 429 Mustang
In 1969, NASCAR was a major influence on automobile sales for the general public. "Winning on Sunday really would sell cars on Monday," Brauer said, so Ford responded by putting a Boss 429 racing engine into its most high-profile car, the Mustang.
The result was the 1969 Ford Boss 429 Mustang, which had a production run of 859 units, every one of which was built by an outside contractor. The current market value is $220,000.
1969 Dodge Charger Daytona Hemi
Ford wasn't the only car manufacturer hoping to capitalize on the sales potential of NASCAR. Dodge wanted in as well. Its bid at that customer segment took the form of what Brauer called "an ultra-aerodynamic version of the Charger."
The car was the fittingly named Charger Daytona, of which only 503 were built. Of those, only 70 had Hemi engines. So if you're looking to buy one today, be prepared to pay something like $400,000.
1971 Plymouth Hemi 'Cuda
When the Plymouth Barracuda debuted in 1964, it was based on the design of the company's sedate Valiant. By 1971, it had been redesigned twice and bore little resemblance to its original manifestation, but the 426 Hemi engine of the affectionately monikered "'Cuda" remained.
Only 119 units of this classic muscle car were made. All of them featured a "shaker hood scoop, wide stance, and some of the best exterior proportions you'll ever see in a vehicle design," Brauer said. Its current market value is $425,000.
1969 Chevrolet Camaro ZL1
In 1969, Chevrolet manufactured just 69 units of the Camaro ZL1. Its 427-cubic-inch aluminum block V-8 engine was assembled by hand, a massive and time-consuming undertaking.
Its low manufacturing run combined with the amount of sheer human labor involved in making a single car made it what Brauer described as "the rarest, most valuable Camaro ever produced." Its current market value is $425,000.
