If you think talking politics is the quickest way to ignite an argument, you haven’t tried classic muscle cars. Which was the first? The quickest? The coolest?

Such questions spark fierce debate among Chevy, Ford, Dodge and Pontiac partisans, with effective jabs coming from the Olds, Buick and even AMC camps. Is it brave or foolish, then, to wade into that mire to label five models as iconic?

The 1964 Pontiac GTO stands out as the icon that started it all, but calling it “the first muscle car” has always been provocative. In the 1961 to 1963 period, Detroit’s Big Three engaged in high-visibility drag-strip duels with specially built, limited-run racecars. They also offered optional high-performance engines for full-size street models, exemplified by Chevy’s “four-speed, dual-quad, Positraction 409,” immortalized by the Beach Boys song “409.”

With the GTO, Pontiac successfully distilled and commercialized the raw excitement of that period in an affordable midsize car, spiked with styling details that conveyed power and speed, such as the faux hood scoops, red-line tires and chrome tailpipe extensions. Not surprisingly, its marketing aimed the GTO at young, single men looking for thrills.

The GTO, then, established the template for what automotive media would call “supercars.” (The “muscle cars” label came much later.) Here are five that earned iconic status by leaving a maximum impact on this unique segment.

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1965 Pontiac GTO
German Medeot/Flickr Creative Commons/CC BY 2.0

1965 Pontiac GTO

Second-year GTO’s sales bonanza exploded the segment.

How many built: 75,352

Starting price: $2,787

Nickname: ‘The Goat’

Current value estimate*: $30,100 to $136,000; convertible: $54,200 to $152,000

One could argue that the 1964 Pontiac GTO’s icon status also applies to later models. But the 1965 version was pivotal. By doubling sales over the ’64, it confirmed an untapped market segment, spurring other brands to jump in and expand customer choices.

A deft restyle gave the ’65 GTO the brand’s signature stacked headlights and a bolder presence. Its 389 cubic-inch V8 engine was bumped up to 335 horsepower. (If you went for the “Tri-Power” triple-carburetor option, you got 360 hp.)  “Cubic inches” refers to an engine’s cylinder displacement, which, before the modern era of fuel injection, computerized controls and widespread use of turbocharging, was a much greater factor in engine output. Generally speaking, the more cubic inches a muscle car engine had, the more fuel and air it could burn to make more power.

Pontiac pushed “The Tiger” nickname in GTO marketing, but owners and fans called it “The Goat.”

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Most competition for ‘65 came from fellow GM divisions, including the first-year Buick Skylark Gran Sport and sophomore-season Oldsmobile 4-4-2. Chevy’s first Chevelle SS396 arrived that year, but it was a teaser with just 201 made.

By then, the GTO had also become something of a pop-culture icon. “GTO” by Ronny & The Daytonas was a #4 pop hit in 1964, and shoe manufacturer Thom McAn issued GTO Shoes in 1965, with an ad boasting that “the heel and sole…were made to grip the accelerator.” (For extra go-go styling, the bottom was designed to look like a slot-car track.) Also that year, on TV’s “I Dream of Jeannie,” astronaut Tony Nelson, played by Larry Hagman, was living a sanitized-for-primetime Playboy fantasy with the coolest job on earth, a house near the beach, a magic harem girl and a GTO in the driveway.

Bill Erdman

1969 Mopars: Plymouth Road Runner Six-Barrel / Dodge Super Bee Six Pack

A menace even to its Hemi big brother.

How many built: Road Runner A12: 1,412   Super Bee A12: 1,907

Starting price: $3,400

Nickname: ‘Six Pack’

Current value estimate: $79,000 to $144,000

For muscle-car fans who wanted a side of intimidation with their speed, the 1969 Dodge and Plymouth “Six Packs” delivered.

Bang-for-the-buck value and a cartoon-character image (including the “Beep! Beep!” horn) drove the 1968 Plymouth Road Runner to quick success. There was, however, a huge gap between its standard 335-hp, 383 cu.-in. engine and optional 425-hp, 426 cu.-in. Hemi, which cost $714 more. Few chose it. The same went for the Road Runner’s corporate cousin, the Dodge Super Bee.  (Plymouth and Dodge were divisions of Chrysler that offered essentially the same muscle cars with different styling.)

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To fill that gap, and to shock the segment as a bonus, Dodge and Plymouth issued the A12 option for 1969. At its heart was an extra-beefy high-performance 440 cu.-in. big-block engine, but with three Holley 2-barrel carburetors instead of the single 4-barrel. Plymouth tagged it Six Barrel, but everyone else called it by the name Dodge used: Six Pack. Dodge’s ad for the car famously proclaimed, “Six Pack to Go!” and Plymouth’s headline touted “Six Barrels on Tap.” The beer metaphors were probably unwise.

With 390 hp, the Six Packs were nearly as quick as their Hemi brethren, but much less expensive and easier to maintain. The A12 package made the cars drag-strip-ready with heavy-duty transmissions and chassis bits. Black-painted steel wheels and a matte-black lift-off fiberglass hood with huge air scoop conveyed a blatant street-racer vibe. Available colors like Limelight, Bahama Yellow and Vitamin C Orange, meanwhile, ensured maximum visibility at the burger drive-through.

1970 Ford Mustang Boss 429
National Motor Museum/Heritage Images/Getty Images

1969-1970 Ford Mustang Boss 429

Ford puts a NASCAR engine in the Mustang.

How many built: 1,350

Starting price: $4,800

Nickname: ‘Boss Nine’

Current value estimate: $207,000 to $430,000

In 1968, Ford lured Semon “Bunkie” Knudsen from General Motors to be its president. Knudsen loved racing, and he wanted faster Mustangs. So, 1969 brought two models named for the new boss’s direct influence: Boss 302 and Boss 429, vastly different cars for different missions.

The Boss 302 was the agile, small-block-powered street version of Ford’s entry in SCCA (Sports Car Club of America) Trans Am road racing. Meanwhile, to qualify a radical new 429 cu.-in. big-block for NASCAR competition, Ford needed to put it into at least 500 retail production cars. Knudsen chose the Mustang.

Although based on the new 429 offered in large Fords and Mercurys, the Boss version was unique with aluminum cylinder heads featuring shallow hemispherical combustion chambers. Because the Boss 429 engine was too wide to fit in the Mustang without considerable modifications, Ford’s exclusive race builder, Kar Kraft, performed the conversions at its facility.

The Boss 429 engine dominated the 1969 NASCAR season, but the 375-hp Mustang production version fell short of expectations. Among changes that tamed the Boss Nine for street use, blunting its potential: conservative specs for the carburetor and camshaft. Low 14-second quarter-mile times were no better than the much cheaper 428 Cobra Jet from Ford’s different and older “FE” engine family and available for any 1969-1970 Mustang.

Despite that, the Boss 429 remains revered as one of the period’s most audacious muscle cars.

Bill Erdman

1970 Chevrolet Chevelle SS454 (LS6)

Chevy catches the Hemi.

How many built: 4,475

Starting price: $4,200

Nickname: ‘LS6’

Current value estimate: $101,000 to $194,000; convertible: $174,000 to $301,000

The muscle car market was a constant game of one-upmanship, yielding ever-higher horsepower under the hood and lower ETs (elapsed times) at the drag strip. Yet, even as buyers clamored for more, the GM brands were, until 1970, hamstrung by a corporate rule capping engine displacement at 400 cu. in. for midsize cars. That was too bad for Chevy fans, who loved the Chevelle’s sleeker body style introduced for 1968—but could not get more than the 375 horsepower the SS396 offered.

Some special-order models got around that rule, including the 1969 “COPO” Chevelle. Ordered through Chevy’s Central Order Production Office system, it had the Corvette’s 425-hp 427 cu.-in. engine, but just a few hundred were built.

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In 1970, GM took the gloves off with the Chevelle SS454. The LS5 version had 360 hp, but the alpha dog was the wilder LS6, jam-packed with drag-race-ready parts and rated at a staggering 450 hp. The one-year-only LS6 Chevelle easily ran with the quickest Mopar Hemis.

The revered and feared SS454 also drove into the pop culture in 1993’s Dazed and Confused, driven by Matthew McConaughey as inveterate partier David Wooderson. And, in 2012, Tom Cruise, as drifter/hero Jack Reacher, did all his own driving stunts in one of these beasts (highly modified for the film).

Bill Erdman

1970-1971 Plymouth Hemi ’Cuda

Beauty and the beast.

How many built: 785 (including 14 convertibles in 1970 and 11 in 1971)

Starting price: $4,100

Current value estimate: $203,000 to $509,000; convertible: $1.55m to $3.15m

Putting the hottest engine in the sexiest body has always been a can’t-miss recipe for muscle-car superstardom, a point emphatically made by the Hemi ’Cuda. Even if it was not the absolute quickest model right out of the showroom, that was beside the point. Nearly a half-century later, “Hemi ’Cuda” remains a conversation stopper.

The Barracuda was an all-new design for 1970 (along with its cousin, the Dodge Challenger), with a far more alluring shape than the previous version. It was a look that seemed born for the smorgasbord of muscle options available for it. The performance version was called ’Cuda. Engine choices ranged from the underrated 275-hp 340 cu.-in. small-block to the all-conquering 425-hp 426 cu.-in. Hemi.

In truth, most speed-seeking ’Cuda buyers were better served by the available 375-hp 440 4-barrel or 390-hp 440 Six-Pack engines. The latter, a new 1970 option, was a bargain at $250 compared to the $871 Hemi. Extracting performance that justified the Hemi’s substantial cost required under-hood maintenance rituals that many couldn’t be bothered with.

But then, just look at it. An idealized mashup of beauty and brawn, the Hemi ’Cuda captured the spirit, charisma and raw performance of the classic muscle-car era like no other.

*All value estimates courtesy of the Hagerty Valuation Tool, with range for cars in #3 to #1 concours condition. Valuations vary widely depending on a vehicle’s condition, rarity, historical originality and previous ownership, among other factors.