6. Buick GNX
The story of this model is an interesting one. Back in 1982, Buick started experimenting with turbocharging its line of standard V6 engines. The results were satisfying, so the Buick engineers got permission to develop a performance version that would deliver better acceleration figures.
Soon, there was the Buick Gran National with 175 HP, which wasn`t impressive, but it was a start. However, in the next couple of years, the Gran National got a bigger engine and more power. This made it go from 175 HP to 200 HP, and finally to 235 HP. With those numbers came acceleration times of less than six seconds, making those black Gran Nationals seriously quick cars.
But in 1987 came the ultimate version they called the GNX, or Gran National Experimental. It featured the same 3.8-liter turbocharged V6, but with 275 HP and 0 to 60 mph times of 4.7 seconds. Nobody expected such a bold move from Buick. After all, Buick was a company for old people producing cars without any excitement.
And suddenly, there was a turbocharged V6 coupe that broke every classic muscle car mold out there. And, it was even faster than a Ferrari. At that moment, the Buick GNX was the fastest accelerating production model in the world. But at $29,000 it wasn’t exactly budget-friendly. However, legend says some owners paid for their cars just by street racing them for money.
5. 1977 Chevrolet Camaro
Like all muscle cars in the ’70s, the Camaro was faced with tightening emissions and safety regulations. This resulted in a loss of power and performance. The early second-generation models looked promising, but just a few years after, they discontinued the Z/28. It was the most powerful V8 model with approximately 165 HP. But it was just a pale shadow of its former glory.
However, the 1977 model is important for two reasons. First, it marked the return of the Z/28 option after a few years of absence. The 1977 Z/28 had just 185 horses but came with a special body kit, wild graphics package and spoiler. However, the second reason is much more interesting. In 1977, Chevrolet Camaro finally outsold the Ford Mustang for the first time since 1967.
The mid 70’s Mustang was a slow, ugly car while the Camaro looked much better with its proper muscle car styling and stance. That is why Chevy sold over 200,000 Camaros that year, while Ford only sold 153,000 Mustangs.
4. Pontiac Trans Am 455 SD
By 1974, almost all muscle cars were extinct from the market, and those who were left were robbed of their power and style. However, there was one model that managed to survive and to offer as much performance and power as possible, and that model was the ’74 Trans Am Super Duty 455.
The year 1974 marked the first restyling of the whole Firebird range, and with new front and the rear end came the improved interior and details. The SD 455 model was carried over from 1973, but it featured better suspension and brakes in the new package. The standard 455 V8 had only 215 HP, but it developed 290 HP in SD trim, which was fantastic for 1974.
3. Chevrolet Camaro IROC
The third-generation Camaro was a well-received, popular car but after a while, buyers wanted more performance and power. So, Chevrolet delivered it in the form of the legendary IROC-Z version. Chevy introduced the IROC-Z in 1985 as a tribute model to the Chevrolet-sponsored International Race of Champions racing series. However, it was much more than just an appearance package with a cool name.
Under the hood was the 350 V8 with 225 HP in the early years and 245 HP in later versions. Buyers could opt for a manual or automatic transmission and they tuned the suspension as well as the steering. Chevrolet even offered a cool-looking convertible which was the first Camaro ragtop in 18 years. The IROC-Z was a popular, influential muscle car that finally brought some real performance to drivers.
2. 1969 Chevrolet Camaro ZL-1
As you may already know, back in the late ’60s, Chevrolet was under the General Motors racing ban. This ban meant that no official Chevrolet products could race and Chevrolet as a manufacturer couldn’t participate in any racing activity. But nobody stopped Chevrolet from helping racing teams through its backdoor programs developing special engines and components. In the late ’60s, the Can-Am was a popular racing series featuring prototype class cars with V8 engines.
Chevrolet wanted to purpose-build a power plant for this championship. So, in 1969, they produced the ZL-1, an all-aluminum 427 big block. It was a high revving, 7.0-liter V8 with around 550 HP in mild tune. Chevrolet produced around 200 of those engines. While most of them went to Can-Am racing teams, they installed 69 of them in C.O.P.O Camaros they sold to drag racing teams.
The Camaro ZL-1 was the same as the regular 1969 Camaro on the outside, but it was so fast, it was barely street legal. The official 1969 Chevrolet literature doesn’t mention the ZL-1 option for the Camaro. However, if you were a successful drag racer or a dealer, you knew about this expensive option. That is why they only made 69 Camaros ZL-1.
1. 1969 Pontiac Firebird Trans Am
In 1969, Pontiac wanted to present a model they could homologate for Trans-Am racing. But, as a part of GM, the factory was still under the racing ban. Still, fans and private teams used many Pontiac products, so the factory wanted to introduce a version they could easily modify for racing. That’s how the Firebird Trans Am came to be.
To mask its intentions, Pontiac introduced the Firebird Trans Am as a loaded version. It featured big-block power from the famous 400 V8 engine equipped with the Ram Air III or IV intake system. The difference between those engines was significant since the Ram Air IV featured improved engine internals and components.
They rated both at 366 HP, which was an understatement. However, this particular version with its signature white paint, blue stripes, Rally II wheels, and other equipment proved to be a tough seller. Sadly, Pontiac only sold 634 Firebird Trans Ams that year. Among those, only eight were convertibles.
These are the greatest classic muscle cars by General Motors. Did you find your favorite? While some of these are still plentiful, others are not. Either way, every one of these gems made their mark on muscle car history.