Z-O Sickness: The History of the Corvette Z06

Speed is addictive. It is an affliction that seems to be permanent because once you’ve been exposed to the sickness, you’re never able to recover. In fact, your desire and need only gets worse. What used to be fast isn’t fast anymore, and you can’t function normally unless you feel that rush of adrenaline pulsing through your blood again and again. For some, it happens from streetlight to streetlight. Guys in all forms of cars take a little hit of the stuff, ripping off 1-2 shifts at several thousand RPM higher than necessary, just for a small dose of the medicine to suppress the sickness. Some guys race cars at the track. They have it bad, too. Mod after mod, sinking thousands of dollars into engines they’ll have to rebuild over and over, constantly in search of a cure that is only ever temporary at best.

At the end of the day, so much of our lives boil down to numbers. How much money is in our paychecks? How much money do we have in the bank? How much does the scale tell us we weigh? How much can we bench press, or leg press, squat or deadlift? What are our macronutrients today? How many hours left in the workday? How much vacation time do we have? How many followers or friends do we have?  How many likes did our lunch photo get? But to those of us that are plagued by the sickness of speed, that obsession with numbers becomes much more focused. How much horsepower does my car make? How much torque? What kind of quarter mile time can we run?  What was our 60-foot time? How much would it cost to squeeze out 100 more horsepower out of this motor? What is our rearend gear ratio? What size tires should I buy for racing? 

There’s no doubt that there is a team of those number obsessed, speed-diseased adrenaline junkies have been working at Chevrolet for a very long time. In the early 1960s there was a chief engineer by the name of Zora Arkus-Duntov, and his addiction to speed would rival anything that Walter White and Jesse Pinkman ever created for anyone. Zora was a former two-time Le Mans winner (albeit in a Porsche, but we won’t hold it against him) before he retired and got the job at GM. Once there, he took serious offense to the AMA ban on factory backed racing that had been in place.  His ideology was essentially; why build fast cars, if you can’t race them? Excellent point Zora, excellent point.  So, when the second generation, aka midyear, Corvette bowed into existence for the 1963 model year, Arkus-Duntov’s addiction whispered in his ear a way around the ban … and a way to cure the itch. That cure was called the Z06 optional package. 

The OG Z: Zora Arkus-Duntov’s masterpiece.

The original Z06 RPO code was nothing more than a box that could be checked by anyone willing to shell out the $1,818.24 extra for the not-racing package. Keeping in mind that a base 1963 Corvette cost just over four grand, it isn’t hard to see why only 199 C2 Z06 Vettes ever rolled off the assembly line. But for nearly 50% more money, owners were treated to just about that same level of superiority over the base model. The Z package got you a vacuum-boosted master cylinder that powered oversized steel brake drums that were finned that sported internal fans, while giant brake ducts channeled air from under the car to the fronts to further help minimize fade under heavy duress. 

Beyond stopping power, the Z06 owner was also treated to a myriad of suspension upgrades, as one might expect from a not-factory racer. The Z got a larger front anti-roll bar as well as heavy-duty shocks and much firmer springs to help it race around … err … run, yeah, run around those long off ramps. 

While most options could be chosen separately, the Z06 box served as an umbrella code to adopt that which Zora and his speed addled crew figured to be paramount and essential. Not the least of which was the 327 cubic-inch L84 V8 that produced a whopping 360-horsepower and incredible 352 pound-feet of torque. And while the 327 could be chosen by a non-Z owner, that engine was coded L76, the main difference being that the Z had the state-of-the-art Rochester mechanical fuel injection instead of a run-of-the-mill four-barrel carburetor. The exhaust manifolds of the two were also slightly different, but both engines ran domed, forged pistons which helped the compression ratio soar to a staggering 11.25:1.  A 36.5-gallon fuel tank was also part of the package, as was a close-ratio four-speed manual transmission and, of course, Positraction at the rear.

 

Spartan interior, even for the ’60s, but no one complained.

Four Z06 models were entered in the LA Times Grand Prix in 1962, Doug Hooper piloted his Z06 and defeated the mighty Cobra (and everyone else for that matter) where it mattered most — at the track on its first try. Sadly, the Z06 option was ceased after only two short years in 1964, amounting to 199 examples built, 78 of which had the giant fuel tank, and only one was a convertible. But the Z did what it was supposed to do, and helped alleviate the symptoms of the speed sickness, at least for a time …

Fast forward forty years. The Corvette is on its fifth-generation, and is a spectacular example of what a modern road-going sports car should be. The C5 was a complete redesign from the ground up, the first of which since the inception of the Corvette in 1953. It was a perfectly balanced fiberglass work of art, powered by a mighty all-aluminum 350 (technically 346) cubic inch LS1 small-block that made 350 (technically 345) horsepower and 350 pound-feet of torque. 

 

2001 brought back the heir to the throne.

But, all was not gingerbread and rainbows for the Vette, because that speed addiction broke out over at Chrysler in the early 1990s and out of that thirst rose a familiar foe to the Bowtie.  Yet another snake-named demon by the name of the Dodge Viper, which for all intents and purposes could have been the Shelby Cobra reincarnate. With a minimum of 450 horsepower, the Viper was a take-no-prisoners track star that beat the Vette in just about every measurable category except comfort. But in a world of speed freak thrill-poppers, comfort comes mostly from winning. 

So, the folks at GM were not happy and willing to rest on their laurels (or tailpipes). They wanted–needed–to make a faster car.  As amazing as the venerable C5 was and would become, it just wasn’t enough. The itch and speed bug was back with a vengeance, and everyone prayed to, and channeled their inner Zora Arkus-Duntov for a cure. Ask and you shall receive. 

 

Electron Blue Looks Good From Any Angle

So, to combat their closest rival (the neo-Cobra), beginning in 2001 team Corvette sent their already svelte fighter back to the gym and what came back was one of the lightest, most powerful and fastest Corvettes to ever come off of a Chevrolet production line. Beginning with the hardtop Corvette, which Chevy deemed to be the stiffest and best handling version of their prize fighter, the main focus of every upgrade was simple: speed. Giving a nod to Corvette nostalgia and the legendary Zora Arkus-Duntov, the new Vette was deemed the Z06. 

The new C5 Z06 lived up to its name. The LS1 engine was upgraded significantly enough to warrant a new designation. Crankcase pressure management was improved, as well as faster oil return to the crankcase, and a higher lift camshaft rounded out the bottom-end improvements, while higher compression 10.5:1 cylinder heads (versus 10.1:1 on the stock LS1), improved airflow thanks to larger ports, bigger injectors, stronger valvesprings, and lighter sodium-filled valve stems helped the new engine rev higher and develop, of course, more horsepower. The upgraded engine’s name, also a nod to the past, was the LS6. The original LS6 was a 454 cubic-inch big-block that pounded out a sickening 425 horsepower and ranks as one of the meanest motors of all time (perhaps only second to the L88). The new LS6 lived up to its name, even if it gave up more than 100 cubic inches to the original. The 2001 Z06 came off the production line making a substantial 385 horsepower, and thanks to just a bit more tweaking, from 2002-2004 the Z06 made 405 horsepower at 6,000 rpm and 400 lb-ft of torque at 4,800 rpm (up 15 lb-ft from the year prior).

 

An upgraded cam and cylinder heads helped the LS6 reach a peak of 405 hp.

Team Vette didn’t just stop at the engine, however. In order to make the most of that extremely stiff body and all that power, Chevy gave the Z06 bigger 265/40/ZR17 front and 295/35ZR18 rear tires (up 20 mm front and rear versus the base Vette), and used a first-ever titanium exhaust system that provided less back pressure and lighter weight. Speaking of lighter weight, that’s just what the Z06 came in at. With a curb weight of only 3,118 pounds and 405 horsepower on tap, the Z had to move only 7.7 pounds per horsepower, edging it ever closer to the big bad Viper’s 6.76 pounds per horsepower. All of these modifications helped make the Z06 blazingly fast by anyone’s standards. It blew through 60 mph in 4.0 seconds flat, 100 mph in 9.5 seconds on its way to a quarter mile time of 12.5 seconds at 115 mph. Top speed, however, was actually lower than the stock C5’s because Chevy augmented the transmission of the Z06 (designated the M12) to have shorter gears for improved acceleration times at the expense of a few top end miles per hour, a tradeoff that worked out very well.

 

This time around, the Z was made to be a race car you could live with everyday.

Production of the C5 Z06 ended in 2004 before the C6 debuted in 2005 (the Z06 name lived on, but in a much nastier car, more on that in a moment). The C5 Z never actually beat the Viper in a straight line race, but what it offered instead was a more complete performance package. It was a factory-racer you could take to the office and then to the track on lunch. It was a car you could pick a date up in, and not have to explain why her shoes were melting to the firewall. At one point, the Z06 was the second fastest car in all the land, which isn’t bad considering the fastest car demanded a $30,000 premium on top of the Z06’s base price of about 50 grand. 

Realizing that the Z-fever was not something that was going away anytime soon, the folks over at Chevy decided to double down and make the C6 version bigger, better, and much badder. In a way that honored its original creator, the C6Z was essentially a production version of the C5R Le Mans race car. They left off the giant wing, but did utilize things like brake cooling vents, functional air scoops to keep the engine breathing easily, and copious amounts of carbon fiber to help with structural rigidity as well as reduce weight. 

 

The mighty C6Z.

What made the C6Z such a throwback, though, was the use of what might be the best engine ever to wear a bowtie badge. The code-named LS7 motor was a monstrous 427 cubic-inch aluminum V8 that produced a sickening 505 horsepower at 6,200 rpm and equally impressive 475 lb ft of torque at 4,800 rpm. This motor wasn’t all top end either, although it did have a redline of a staggering 7,100 rpm (try that with your ’67 big-block), it also produced 385 lb-ft of twist barely off idle at 1,600 rpm, and maintained 400 lb-ft between 2,400-6,400 rpm. Backing up that power was your choice of any transmission you wanted, so long as what you wanted was a six-speed manual. As expected, that trans came with a corresponding heartier clutch and drivetrain parts to handle the massive power. 

 

The heroic LS7: a ‘small-block’ 427 that made 505 hp and redlined at 7,000 rpm.

Of course all that sickening addictive power would be useless if it couldn’t be used out on the track from time to time.  So, engineers made sure that they upped the oil capacity to eight quarts (versus the base C6’s 5.5) using a dry sump lubrication system with an oil tank mounted where the base C6 keeps its battery. In addition, they made sure that literally every fluid except brake fluid had a cooler to help temperatures stay manageable under the high stresses of racing — the C6Z was the real deal at the track. 

But to be a true supercar killer, the Z also had to be able to slow down as well as it could go.  Massive 14-inch front rotors were grabbed by six-piston calipers, while the rear 13.4-inch rotors were handled by four-piston clamps. Both front and rears calipers were painted red, basically a C6Z signature, and the result of this system could have doubled as a parachute when it was put to work on the track. 

The C6Z was a true race car for the street.

The C6Z did use much of the same suspension as its lesser sibling, but did get larger sway bars, stiffer springs, model specific dampers, and much bigger rims and rubber (275/35ZR18s up front and 325/30ZR19s at the rear). The big difference between the base C6 and the Z was that the Z06 used predominantly aluminum for the chassis as opposed to the base model using steel. The Z also got a fixed cast-magnesium roof in favor of the base car’s removable (and much more fun) roof. The resulting effect was as one might expect – significantly less weight to the tune of 141 pounds trimmed from the base model for a total of 3,147 to be exact.  Just for reference, the race-bred Ferrari 458 Italia clocks in at 3,274 pounds.   

If speed really is addictive, the C6Z at redline was nothing short of intoxicating — capable of a euphoria that would make even Walter White wonder how it could get people so hooked. For only about $80,000 brand new, the 2006-2014 Z06 was the best money you could spend if what you wanted was to go, and go like hell. So how fast was fast?  How about 0-60 mph in a mere 3.4 seconds, 0-100 mph in 7.4 blistering seconds, past the quarter mile in only 11.4 seconds at 123 mph, all the way up to a top speed of 198 mph? It then drops from 70-0 mph in only 153 feet, and, oh by the way, can pull a 1.01 g around the skidpad. Stop, go, turn — check, check, check. 

A functional hood and side scoops helped the C6Z stay cool during any race. Planned or impromptu, the Z was always ready.

This car was ready to race, and for the money, there was no better bargain for your speed fix anywhere in the world for about an eight-year span. But all things must come to an end, even mania-inducing hypercars capable of producing so much smiling, onlookers will wonder if the driver even has a functioning central nervous system. So in 2013, we bid adieu to one of the most awe-inspiring cars Chevy had ever produced, and it left us with wild pangs of withdrawal … but not for long. 

Even with the advent of the new exotic looking C7 in 2014, and as impressive as the direct-injection 455-horsepower LT1 engine was, we still couldn’t quite shake this quiet, yet clearly apparent itch just beneath the skin. The C6Z left us with proof that the speed sickness was in our blood for good, and there was no getting rid of it. We were hooked, and though we were satiated for some time with the prodigious power of that massive 427 cubic inch drug factory, after almost a decade, the effect began to wear off. Somehow, even with a 200 mph car, we were starting to build up a tolerance to it, and so it seems, were the folks over at GM. 

So, only a year into its life, those Bow Tie drug dealers couldn’t resist any longer either. And unlike us eager by-standing junkies, those fanatical, obsessive, passionate, and thoroughly speed-hooked cooks decided to unveil a car so sinister it should be illegal. 

The world beating C7Z.

The C7 Z06 is nothing short of stupid fast, and as addictions go, it might as well come with a free methadone clinic membership. For the latest and greatest Z, GM has pulled out all the options.  Want a Z06 convertible? Done. Need a Z06 with an automatic transmission?  Done (why?). There are three different trim levels (1LZ, 2LZ, and 3LZ), as well as three separate aero packages, topped off by the top of the line ZO7 option package, which makes the C7Z essentially an all-out race car that you can put a license plate on. Michelin Pilot Sport Cup 2 summer tires (P285/30ZR19s up front and P335/25ZR20s out back) have just enough tread to technically be legal, replacing the somehow not-quite-sticky-enough base Michelin Pilot Super Sports. The suspension gets an even-more track ready tune, and the 14.6-inch front and 14.4-inch rear brakes get supplanted for carbon ceramic brakes (15.5-inch fronts and 15.3-inch rears) and other aero bits like a lip spoiler, and transparent wicker bill on the rear spoiler, to further increase downforce.  

When a car’s stance screams: “I dare you.”

For the C7, GM elected to resurrect the 1990s LT1 motor nameplate (which can be traced back to the early ’70s), and just as the 1996 Grand Sport got a modified version of the LT1 called the LT4, so does the Z now mirror that same upgrade, except in a much, much more insane way.  The new LT4 is a 6.2-liter supercharged and intercooled all-aluminum, direct-injected V8 engine, that is the most powerful motor ever produced by the General outside of the latest ZR1. The numbers speak for themselves. 650 horsepower at 6,400 rpm and a matching 650 lb-ft of torque at 3,600 rpm. Backing up that massive power is your choice of either a 7-speed manual with automatic rev-matching or 8-speed automatic. 

The resurrected LT4 makes just about double the power of what the C4 version did.

There is even an onboard performance data recorder that logs video of your escapades and keeps performance data in real-time. One drive and you’ll see just how habit-forming speed can be. You’ll need every second of video to look back on because there’s a good chance you could be in jail before you even know what happened. 0-60 mph in the C7Z takes a scant 3.0 seconds, 0-100 mph takes a scary 6.8 seconds, it goes through the quarter-mile in 11.1 seconds at 127 mph and tops out at a downforce-induced 190 mph. Stopping from 70-0 mph takes only 128 feet and the Z goes around the skidpad to the tune of a mind and body-bending 1.19 g. And even at 3,524 pounds for the coupe and 3,582 for the convertible, the Z still manages to get 13/24 city/highway mpg — presuming you can exercise some self-restraint.   

The C7Z not only benefits technological advancements to the C7, but also happens to be the benefactor of its interior as well. While, it may be a cold-blooded race car, you can still enjoy things like heated and ventilated seats, dual climate control, Napa leather, an 8-inch LCD display, 4G LTE Wi-Fi connectivity, Bluetooth, and either Apple CarPlay or Android Auto, all on the way to the track to embarrass a few GT350s. For a starting price of $79,500, we dare you to find any car on earth that will give you the same high as the C7Z. Look all you want, you won’t find one. The C7Z is the ultimate track car that lives up to its heritage, and nothing else even comes close. 

Even though it is a race car in every sense of the word, the C7Z can still be a comfy road trip car.

While so much of our lives comes down to numbers, for speed-freaks, those numbers mean even more. We are plagued by an ever-present urge to go just a little faster, and no matter how much faster we go, it’s never quite enough after a while. Zora Arkus-Duntov knew it, just as we do. He took an already addictingly-fast Corvette and created the Z06 option as an even purer stimulant subdivision. And now with a deliriously fast 650-horsepower car that posts disgustingly nauseating specs and numbers, that should be enough, right? Nope. Speed is a drug, and with the new ZR1 out on the prowl, the Z06 already has been bested by its own sibling. No one knows what will come out next from inside of those well-guarded walls of General Motors, but one thing is certain: the speed sickness epidemic is alive and spreading, fast. 

The first drop-top Z since the ’60s.

 

Corvettes in your inbox.

Build your own custom newsletter with the content you love from Corvette Online, directly to your inbox, absolutely FREE!

Free WordPress Themes
Corvette Online NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

Corvette Online - Corvette Enthusiast Magazine

We'll send you the most interesting Corvette Online articles, news, car features, and videos every week.

Corvette Online - Corvette Enthusiast Magazine

Corvette Online NEWSLETTER - SIGN UP FREE!

We will safeguard your e-mail and only send content you request.

Corvette Online - Corvette Enthusiast Magazine

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...



Late Model LS Vehicles

Classic Chevy Magazine

Performance Driving

Corvette Online - Corvette Enthusiast Magazine

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...

  • Late Model LS Vehicles
  • Classic Chevy Magazine
  • Performance Driving

Corvette Online - Corvette Enthusiast Magazine

Thank you for your subscription.

Thank you for your subscription.

Corvette Online - Corvette Enthusiast Magazine

Thank you for your subscription.

Thank you for your subscription.

Loading