Ready, Vette, Go: C4 ZR-1 and C5 Z06 bring bang for the buck
Metallic exhaust roar echoed through the hillside as I wound along Ohio’s Kokosing River. Overhead cams whirred and the engine swept through its sweet spot between 4500 and 6500 rpm. Shifting at redline, I was rewarded by another eager rush in the meat of the powerband. It’s hard to believe this is a big American V-8. Now, as in 1990, the Chevrolet Corvette ZR-1 is a revelation.
So revelatory, in fact, that it shocked General Motors’ own engine division into a frenzy of activity. GM engineers were so taken aback at the decision from on high to hire Lotus to design the ZR-1’s high-performance LT5 engine—and Mercury Marine for its construction—that they quickly got to work on new small-block V-8 designs. The result was in the car behind us, a 2004 Corvette Z06.
These two bygone bosses of Bowling Green obviously have a lot in common—flip-up headlamps, about 400 horses under their hoods, and capable handling. Here’s something else: Both can be had today in excellent condition for around $45,000, according to the latest Hagerty Price Guide. That’s quite a steal considering the recent run-up for other performance cars of the era (a roughly contemporary Toyota Supra Turbo, for instance, will easily run you six figures).
Of course, we couldn’t help but wonder which Vette is better. Father and son Hagerty members Rick and Rocky Yusi own pristine, low-mile examples of each and graciously shared them to help us understand what sets these cars apart. Together, we disappeared into the hills of southeast Ohio to find answers.
Engaging with a C4 Corvette is an exercise in immersion. Or maybe it’s contortion. Slide over the famously large sill and slither down into the deeply bolstered bucket seat, and you’re completely enveloped by a high transmission tunnel and driver-oriented dash. You’re now of this Corvette, not merely in it.
Nowadays this cockpit—complete with orange-over-charcoal analog gauges, digital display, and acres of small buttons—screams RADwood. But in period, the futuristic design ethic was intended to break completely with prior generations of America’s sports car. “The C4 was a modern statement: It didn’t look back at heritage,” retired GM designer John Cafaro told me in a phone interview.
Brash as it is, there’s not much to the cabin or the design as a whole that tips off the casual observer that this version of the Corvette is a supercar slayer. “I love the way it looks and all the subtle ways it’s different from the base car, but I do wish Chevy made it stand out a bit more,” admitted Rick, who bought this ZR-1 new in 1990. The tachometer’s 7000-rpm redline is the only hint at the marvel that is under the clamshell hood.
The standard Corvette in 1990 had a pushrod, iron-block 5.7-liter L98 V-8 that produced 245 horsepower at 4000 rpm. The ZR-1’s engine, known as the LT5, carried over only the displacement and bore spacing. Its block and cylinder heads were aluminum. Dual overhead cams actuated 32 valves (versus 16 in the standard car). It made 375 horsepower at 5800 rpm—around the fuel cutoff for the standard car.
I fired up the LT5 and left the college-town charm of Wooster via a sweeping state route dotted with Amish farms. The bucket seat cosseted me with a vast array of power and pneumatic adjustments. Meanwhile, the three-way adjustable Selective Ride Control dampers—a feature that debuted on the ZR-1 and paved the way for similar tech in later models—impressively blunted road imperfections when set to Touring, the softest mode.
Along with that comfort, though, comes some softness in the controls. This is a car from a different era, after all. Initial application of the brake pedal is 1990s-GM squishy, although it firms up with increased pressure. The weighty, mechanical shifter atop the ZF six-speed box has a rubbery give as you reach each detent.
The asphalt roller coaster bends began south of Millersburg, where the scenery evolved from undulating corn and soy fields to rocky, rolling hills. I stiffened the ZR-1’s damper settings to Sport and then to Performance. Even in modern cars, selectable drive modes can be more gimmick than substance, but not here. The dampers deftly responded to imperfections and helped the car stay utterly poised as I pitched from left to right.
The harder you drive the ZR-1, though, the more it reveals the one dynamic trait that belies its age: the chassis itself. At anything more than about 6/10ths pace, the frame flexes through camber changes. The car never gets upset, but when pushed, the compliant chassis’ additional motion distracts from the experience. Turning the ride control setting from Performance down to Sport softens the dampers, enabling smoother, less wobbly transitions, yet I found myself wondering how much more dynamic the ZR-1 would feel had its structure been further stiffened to let that superb suspension more effectively do its job.
Despite that, I emerged from the twisty river-bottom roads with some newfound respect for the ZR-1. Remember: Less than a decade prior to this car’s debut, the Corvette was a still 190-hp weakling. This car made clear that Chevrolet wanted to build a world-class sports car, and the seriousness of that intention still shines through when you’re driving it today.
On to the Z06. The design is clearly less of a departure from what had come before than the C4. The General Motors that developed the C5 in the 1990s was more cautious—and had a considerably smaller pocketbook—than the one that had spawned the C4 in the early ’80s. Cafaro, who was chief designer for the C5, noted that special care had to be taken to appease various departments, including what he affectionately calls “the toothpaste and detergent folks” in marketing. “One little controversy could’ve killed the car,” he said. By 2004, the C5’s last year, Chevy had relaxed enough to allow a carbon-fiber hood and stripe package for the Commemorative Edition, as on the Yusis’ car. Today it’s worth slightly more than other C5 Z06s.
Styling aside, the generational difference from the ZR-1 immediately presented itself upon opening the door: Those massive side sills are gone. You can simply get into the car without first having to practice yoga.
Those sills shrank because the C5’s chassis, four times stiffer, incorporated hydro-formed frame rails and a strengthened center tunnel. The concerted effort to increase rigidity went hand in hand with making the C5 accessible to a wider array of people. A longer wheelbase increased cabin space, as did repositioning the gas tanks to behind the seats.
Most of that practicality carried over to the high-performance Z06, which debuted in 2001. The Z06’s flat, wide seats surely did better in focus groups than the ZR-1’s, since they’re able to take in a broad swath of humanity, although they don’t hold you nearly as well in aggressive maneuvers. (Sport buckets, available in the base coupe and convertible, didn’t make it into the Z06 due to their extra weight.) Those same focus groups also nixed the pseudo-digital gauges, so you stare at more traditional analog gauges. As a result of the efforts to make the C5 more approachable, the Z06 feels more utilitarian and less of an occasion than the ZR-1.
At least, until you fire up the 405-horse, 5.7-liter V-8. The standard, lightweight titanium exhaust emitted a docile burble that turned raw and throaty when I rolled onto the throttle. The LS6, as this engine is known, is on its face less exotic than the ZR-1’s LT5: It’s a pushrod engine and makes only 55 horsepower more than the contemporary base Corvette. Yet that only speaks to how profoundly the tried-and-true small-block had changed in the intervening years. The LS-series V-8, which debuted with the C5 for 1997 and eventually proliferated to millions of trucks and SUVs (not to mention hot rods and restomods of all stripes), was the most significant update to GM’s bread-and-butter V-8 since it debuted in the 1950s. An aluminum block was baked in from the start, as were high-compression aluminum cylinder heads.
The LS6 was the first true rock star of this engine family, with even higher (10.5:1) compression, better-breathing intake manifold and cylinder heads, and myriad tweaks to the internals. The result is an engine that pulls linearly—and hard—from about 2000 rpm and barely lets up by its 6500-rpm red-line. You can rev it out or stick the gearbox in third or fourth and count on low-end torque to muscle through a corner.
The Z06’s controls would be at home in a current sports car. Moderately heavy steering offers feedback but isn’t particularly lively—for better and for worse, it’s similar to many modern racks. The shifter’s throws are long but crisper than in the ZR-1. The brakes inspire confidence with a firm and linear pedal. And, thanks to the relocation of the transmission to the rear of the car, the Z06’s footbox allows plenty of room for fancy pedal work.
Returning to the route along the Kokosing, I discover how progressive and predictable the Z06 is, especially for something with this much brawn. The nonadjustable suspension allows for plenty of body roll in assertive driving, but it’s always well composed. You quickly get used to this trait, and it becomes part of how you set the car through a corner. The chassis does exhibit some flex, but it’s dramatically less than the ZR-1’s. Overall, the 3100-pound Z06 feels big but never unwieldy, even on tight, technical roads.
As the day ended, I slotted the Z06’s shifter into sixth gear and settled into a cruise. The car quietly soaked up the miles and nosed close to 30 mpg at the speed limit. It was almost funny; in contrast to the ZR-1, the only thing I needed to adjust to bring out the Z06’s differing personalities was what gear I was in.
What we have here, despite the apparent similarities and comparable values, are two very different slices of apple pie. The ZR-1 is more complex and full of character. It is also, from a design and historical standpoint, more significant—we’re talking about the first Corvette in decades that truly went toe-to-toe with the best in the world. Perhaps for those reasons, trailer-queen ZR-1s tend to fetch considerably more than similarly pampered Z06s.
If you’re looking to drive a lot, it’s hard to argue with a Z06. Say what you will about GM’s obsession at the time with metrics and ergonomics; it yielded a sports car you can still easily use every day to fetch groceries—and then embarrass younger and more expensive cars at a weekend track day. It’s truly a Goldilocks car. That versatility and usability help explain why it’s generally appreciating faster than the ZR-1—and why we put it on our most recent Bull Market List.
Ultimately, both exude “Corvette” and offer heaps of performance and personality. I end the day still wondering which $45K classic I would choose, but more so, I’m grateful to have experienced them both.
This article first appeared in Hagerty Drivers Club magazine. Click here to subscribe and join the club.