Those buff, but overweight power rides born of the ’60s are taching up again with less flab, better fuel economy and impeccable road manners

There wasn’t much left but rust when Tim Cooley found the remains of the old ’34 Ford three-window coupe. He spent the next few years hammering out the dents, fixing the broken glass and replacing the rusted fenders. But as he sits idling on the side of Detroit’s Woodward Avenue, the big V-8 under the hood burbling menacingly, Cooley says it was worth every minute—and dime. The retiree from Clarkston, Michigan, spent much of his time cruising Woodward Avenue back in the 1960s and ’70s, but usually riding shotgun in someone else’s car. “I always rode here when I was a kid,” he recalls. “Now that I have something worth showing, it’s even more fun.”

Cooley was one of the more than 40,000 hot rod, sports car and muscle car owners who turned out for the 20th annual Woodward Dream Cruise in August—another million fans lining miles of the eight-lane boulevard to get a glimpse of the action. The unlikely outgrowth of a local car club’s yearly summer jamboree, the Cruise has become the single-largest automotive event in the country, perhaps the world, and serves up a strong sign that the American love affair with the automobile is far from over.

The focus is on muscle, and for good reason considering Woodward Avenue’s history as more than just the artery linking the Motor City and its northern suburbs. While the classic film, American Graffiti, might have focused the spotlight on California’s cruising scene, Woodward was where the real action took place almost every summer night during the halcyon years of the American auto industry. Indeed, it was commonplace to see not only local teens parading around in their hot rods and muscle cars, but any number of “suits” from General Motors, Ford and Chrysler. Woodward was the first place legendary automotive bad boy John DeLorean went to see whether his badass new Pontiac GTO could smoke the best offerings from Ford and Chrysler when the light turned green.

Conventional wisdom would suggest that the golden age of the muscle car was already a fading memory by the late-1970s, and there’s no question that plenty of classic performance models, such as the GTO and the original Dodge Challenger didn’t last much beyond the second Mideast oil crisis. There’s little doubt that rising fuel costs were a major factor in their demise, as was the “double-nickel” speed limit, along with increased police enforcement. Insurance companies didn’t help either, making coverage all but unaffordable for those with Hemi V-8s, Hurst shifters and shaker hoods.

With new federal fuel economy standards in place, the opening of the 1980s saw the virtual demise of the “eight-banger” (V-8 engine). Even survivors like the Ford Mustang largely migrated to smaller, staid V-6s. But by decade’s end, there were glimmers of hope. Even though federal law set a national speed limit of 55 mph—and, for a time, even required automakers to top off their speedometers at a mere 80 mph—plenty of folks ignored the new rules, and a savvy driver could figure out how fast they were going in cars like the reborn Mustang GT simply by checking the tach and doing some quick math as they hammered through the gears.

Slowly, in fits and starts, automakers began to pump more power back under the hood, some reviving their big V-8s, others opting for more sophisticated alternatives, such as turbocharging and supercharging. By the turn of the millennium, even with tough new emissions and fuel economy regulations looming, the pace rapidly accelerated. Though an attempt to bring back the GTO—the “Goat,” to its loyal fans—failed, Chevrolet scored a smash hit with the 2009 revival of the Camaro. Dodge threw down the gauntlet with the resurrection of the Charger, and then the Challenger. And Ford started finding ways to pump up the testosterone of its classic pony car with spin-offs such as the Shelby Cobra.

For those who still aren’t convinced that this is a new golden era of muscle, you only need check out the 2015 Dodge Challenger SRT Hellcat. By the time you read that sentence, you could have launched this fire-breathing monster from 0 to 60—as we discovered during a trip to Portland for a day of driving that included several hours of track time at Portland International Raceway. Harnessing Chrysler’s first-ever supercharged Hemi V-8, this 6.2-liter brute churns out a vein-popping 707 horsepower, enough to have left nearly 100 feet of charred rubber on the tarmac, tire smoke wafting over the pit lanes.

There is an automotive arms race underway that would have seemed daunting even by ’60s and ’70s standards. In fact, if you’ve got a fat enough checkbook, Shelby America will deliver you a 1,000-horsepower “tuned” version of the Mustang, and for something more exotic—and far more expensive—you can push even higher with exotic supercars such as the Bugatti Veyron and Koenigsegg Agera One:1. In the days when Detroit dominated American highways, 0-to-60 times of four seconds were barely being achieved anywhere but on the drag strips. Today, you can get down into the low two-second range with Japan’s two-seat Godzilla, the Nissan GT-R.

Purists might take offense at lumping them all together as “muscle cars,” and they’d be right…to a point. You won’t confuse a Bugatti or even a GT-R with a classic piece of Detroit iron, but even modern incarnations of the Challenger, the newly updated Mustang and the “C7” Chevrolet Corvette Stingray are very different beasts from those that once ruled Woodward Avenue and other cruiser hangouts nearly a half century ago. The classic muscle cars of yore typically did only one thing well: they were rockets off the line, but trying to take a sharp corner or simply squeal to a stop at the next red light was always in doubt.

Aerodynamics were an afterthought—the fourth-generation ’Vette actually did better in the wind tunnel facing backwards. And if your fuel economy even came close to double-digits you could count yourself lucky. These rides were likely to overheat in the summer, and bringing them out on a cold winter’s day wasn’t something for the faint of heart.

Today’s muscle cars are, by comparison, angels on the highway, demons on the track, even the most extreme machines are designed to be “everyday drivers.” They’re likely to be equipped with many of the latest safety features, and quite a few now offer all-wheel drive. Swap out those performance tires for a pair of Bridgestone Blizzaks and you’ll hang with the Jeeps when there’s snow on the ground. Sure, you’ll likely be looking at a stiff insurance premium, but even the Challenger Hellcat can be surprisingly tame when you want it to be, simply by switching from track to comfort mode.

“These are muscle cars without the compromises of 40 years ago,” says Dave Sullivan, an analyst with consulting firm AutoPacific, Inc. And the timing couldn’t be better, he quickly adds, noting that demand is surging as Baby Boomers approach retirement. They’ve raised their families, put away some cash, and “are looking forward to having a little fun as they approach retirement.”

But how much longer can the fun continue? It remains to be seen whether this performance revival will last much longer than the original muscle car era.

Automakers around the world are facing some serious challenges in the form of new emissions and fuel economy regulations, the American Corporate Average Fuel Economy standard, or CAFE, set to shoot upwards to a seemingly unreachable 54 mpg by 2025. That’s a number that even the most anemic hybrids couldn’t make a decade ago. Chevy’s new Stingray, however, is already delivering a stunning 30 miles a gallon on the highway—the sort of number even a Corvair struggled to make in the supposed golden age of muscle. And then there’s the Tesla Model S, able to jump off the line as fast as a Porsche 911 without using any gas at all. Both the ’Vette and the Tesla sedan suggest that muscle isn’t going to go away, thanks to some radical changes in powertrain technology and other vehicle improvements.

Redesigned for 2014, Chevy’s two-seater adopts such advanced systems as direct injection and displacement on demand, the former delivering more muscle for less fuel, the latter disabling half of the engine’s cylinders when the demand for power is light, such as cruising down the highway. Tesla’s sleek sedan, meanwhile, opts for an all-electric drivetrain powered by up to 84 kilowatt-hours of lithium-ion batteries. And it shows that the conventional wisdom is wrong when it comes to high performance.

There’s an old adage among gearheads: “There’s no replacement for displacement.” And there’ll likely be some big eights, and even some 10- and 12-cylinder engines that survive, but going forward, count on turbocharging and electrification, rather than classic, big-block engines, to allow performance cars to survive in an era of tough government mandates.

BMW’s new M3 sedan and M4 coupe are faster than ever despite their newly downsized engines, both sharing a new twin-turbo, inline-six that churns out a hefty 425 horsepower and 406 pound-feet of torque. “Blowers” have been around since Bentley fielded a supercharged racecar at Le Mans, the legendary Blower Bentley, nine decades ago. But forced air induction has only recently become a serious alternative thanks to some major enhancements that improve reliability and eliminate drawbacks such as turbo lag—that annoying pause between the time you stomp the throttle and the power kicks in. By some estimates, more than half of all vehicles could adopt super- or turbocharging over the next decade. And that’s not just for downsized engines. The massive Challenger Hellcat uses a supercharger to add a couple 100 more horsepower than the same basic 6.2-liter V-8 in the still-menacing Challenger SRT.

Turbochargers have the advantage of reducing fuel consumption when driven less aggressively. But there are other ways to deliver even more menacing—yet enviro-friendly—results. The new BMW i8 produces a pavement-pounding 357 hp and 420 lb-ft of torque, yet the EPA says it will get up to 76 mpg. Credit the unique powertrain layout of the maker’s new, carbon-fiber-bodied, plug-in hybrid. At the heart of this high-tech beast is a complex package that pairs a pint-sized three-cylinder turbocharged gas engine with two electric motors. The i8 can operate in a variety of modes, from pure electric to sport, the latter combining all three sources of power.

“Electrification” isn’t just for mileage misers anymore. In fact, battery power has some distinct advantages that have caught the interest of a growing number of performance fans. Just switch on your blender and you’ll get an idea. Electric motors develop maximum tire-spinning torque the moment you switch them on, unlike an internal combustion engine that needs to rev up.

The new La Ferrari and McLaren P1 both have adopted Formula One–derived hybrid systems. The new Porsche 918 Spyder has gone with a 608-horsepower plug-in hybrid driveline that launches from 0 to 60 in a mere 2.7 seconds, and 186 mph in 22 seconds. BMW, Nissan and even Chevrolet are among the many manufacturers who are rumored to be studying the potential of high-performance hybrids in the near future. Acura will use a unique gas-electric layout with the 2016 revival of its NSX supercar: a turbocharged six-cylinder engine paired with an electric motor driving the rear axle, with two more motors up front, one for each wheel. The layout will offer the ability to “torque vector”; by directing extra power to the outer front wheel, it will help steer the two-seater through sharp corners.

Whether using electric motors or conventional mechanical systems, such modern muscle cars as the new 467-horsepower Lexus RC F coupe are not only able to put their power to the pavement but help you use it to corner, rather than just launch in a straight line. The Japanese maker offers both a Torsen differential to shift power to the wheels that need traction the most, as well as a more sophisticated system it dubs a Torque Vectoring Differential. And the coupe offers a trick digital display in the instrument cluster to show the driver what’s happening.

The new RC F illustrates another, somewhat controversial, change sweeping through the modern performance market. A half-century ago, no serious cruiser would have been seen on the street without a Hurst shifter. But despite a grassroots campaign to “Save the Manual,” stick shifts appear to be a seriously endangered species. The Japanese maker is only offering an automatic, even on the performance version of its new coupe—and it’s not alone. Ferrari hasn’t offered a manual in several years, nor has Lamborghini, nor Maserati. “Younger people don’t even know how to drive a stick,” laments Lexus marketing chief Brian Bolain.

While purists may weep, there’s a good reason why even a growing number of traditionalists have shifted gears, so to speak. The latest generation of six-, eight- and even nine-speed automatic transmissions has overcome many of the performance problems of older packages. They can be smooth and blindingly quick, while also delivering better mileage than a stick. And then there are the motor sports-derived double-clutch packages, such as Porsche’s PDK—short for the German tongue-twisting Porsche Doppelkuppling. Think of these as electrically shifted manuals. The clutch and shifter may be gone, but you still get the option of going hands-on with steering wheel–mounted paddle-shifters. And even if you stick to fully automatic mode, the Porsche 911 S with PDK will hit 60 about two-tenths of a second faster than with a seven-speed stick.

A long list of additional improvements that make today’s muscle cars even better than those of the golden era, whether you’re measuring raw horsepower, lap times, cornering G-forces—or everyday driveability. More modern steering systems, better tires, improved aerodynamics and advanced lightweight materials, to name a few. Today’s performance cars make extensive use of ultra-high-strength steels, and even aluminum and carbon fiber, to improve rigidity, delivering both better handling and improved ride comfort. And lighter vehicles also get better fuel economy.

The bottom line is that muscle car fans have plenty to cheer about. They’ve got a far wider selection of vehicles to choose from than ever before, emphasizes AutoPacific analyst Sullivan, “Whether you want something that’s retro, like the Dodge Challenger, or modern and European, like the BMW M3.” They’re generally quicker, more reliable, safer and far more fuel-efficient. So, who says the golden age is gone? As the classic song once suggested, “These are the good old days.”

Paul A. Eisenstein is a publisher of the website TheDetroitBureau.com.