From an acclaimed concept car John DeLorean reportedly dismissed because he wanted something “smaller and more European,” to the design that ended a feud between a pair of GM giants — but may have set the Corvette back decades — a trove of unique documents, sketches and models tells a secret history of the 60-year quest to build a mid engine Chevrolet Corvette.
The story begins in the late 1950s with legendary Corvette chief engineer Zora Arkus-Duntov and came to fruition when the first mid engine 2020 Corvette Stingray sold for $3 million at auction in January.
Titled “The Vision Realized: 60 Years of Mid engine Corvette Design” and created by GM Design Archive & Collections, the exhibit included 19 original sketches by designers including Larry Shinoda and Tom Peters, the massive 4-Rotor rotary engine from the 1973 Aerovette engineering, a wood wind-tunnel model, even letters from Arkus-Duntov’s personal files.
“The story of the mid engine Corvette is incredibly complicated, full of fits and starts,” said Christo Datini, manager of the GM Design Archive & Collections.
Cristo Datini at the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020 (Photo: Eric Seals, Detroit Free Press)
A mid engine Corvette was a dream shared by GM designers and engineers. The layout, in which the engine is behind the passenger compartment and immediately over the rear wheels, improves acceleration and handling. It’s been a mainstay at Ferrari for decades, and inspired repeated design and engineering projects at GM. None of them made it to production till now, largely because the Corvette’s original front-engine layout was so successful.
“Why would we change the Corvette?” GM chairman and CEO Richard Gerstenberg said to Arkus-Duntov before both men retired in the mid-1970s. “We sell every one we can make.”
‘Design without limit’
A generation of GM designers and engineers had already fought that attitude toward the sports car that debuted in 1953 model, and a couple more would before the midengine eighth-generation C8 Corvette Stingray debuted last year.
The exhibition included dozens of sketches, models, photos and documents.
“Our mission is to preserve the heritage of GM Design and educate our designers on GM’s prominence in the world of design,” Datini said. The archive also is working with the Detroit Institute of Arts on a massive exhibition dedicated to automotive design that opens this summer.
The Corvette exhibition closed at the end of January, but elements of it are likely to be displayed at other events and locations, possibly including the National Corvette Museum in Bowling Green, Kentucky, which provided materials for the collection.
Original magazines with drawings of what Corvettes could have looked like on display at the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020 (Photo: Eric Seals, Detroit Free Press)
Chevrolet Engineering Research Vehicle I, Also called SERV I and XP-708, was the beginning. A running model that debuted in 1960, the car had the looks of an Indy car and a chassis that tested what a midengine layout could do. It was “a design without limit” and an “admirable tool” to help Chevy figure out “what to put in Corvette,” said Duntov, himself a former driver in the 24 Hours of Le Mans sports car race.
CERV I was used as a test vehicle for years. Larry Shinoda, who would go on to be known as the father of the ’63 Corvette Stingray and the Mako Shark concept car, tweaked its design repeatedly as engineers tested it with seven different power trains.
GM eventually retired CERV I, selling it to the Briggs Cunningham Automotive Museum for $1. When the museum failed in the 1980s, GM bought it back for “somewhat more,” Datini said.
A model of the 1968 Chevrolet mid-engine Corvette Roadster that is one of many items for General Motors workers to see at the Corvette design display at the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020 (Photo: Eric Seals, Detroit Free Press)
Corvettes the world never saw
Shortly thereafter, Duntov heard rumors Ford was developing a Le Mans racer to challenge Ferrari and launched work on CERV II. GM decided not to race, Ford and Carroll Shelby built the GT40 that inspired “Ford vs. Ferrari,” and the CERV II was used as an engineering test bed at secret proving grounds and never seen by the public during its active lifetime. Built in 1964, CERV II had a 500-horsepower V8, 210-mph top speed and 2.8-second 0-60 mph time.
A picture of the CERV II Corvette. The sports car never went into production but it was influential in the design of the C5 production Corvette. (Photo: Eric Seals, Detroit Free Press)
“By that time, engineers and designers knew a midengine chassis was necessary” to get maximum performance from the ‘Vette, Datini said. Putting the engine behind the passenger compartment puts the car’s weight over the rear wheels to put down more power without spinning. Shifting balance from the production ‘Vette’s nose-heavy weight distribution would also improve handling.
Also in 1964, the XP-819 experimental car was being tested. Designed by Shinoda, it bore a strong resemblance to 1970 Corvettes, but Duntov hated it, calling it an “ugly duckling” at least in part because he wished his engineering team got some of the budget allotted to designing the car. It had a 327 cubic-inch V8 and pop-up headlights.
Like many concept and engineering vehicles, XP-819 was destroyed, chopped up. Years later, the pieces were found in NASCAR designer and mechanic Smokey Yunick’s garage.
Half Corvette, half Porsche
With a name GM would later recycle on a minivan, the Astro II XP-880 was never publicly identified as a Corvette, but it was one, intended for production in 1970, but never got there. It debuted at the New York auto show, featuring a nose, front fenders and Firefrost Blue paint that that foreshadowed 1970s production cars.
DeLorean, then Chevrolet general manager, asked for a rush program to create a different midengine design to match the midengine Pantera Ford was developing with Italian sports car maker De Tomaso to debut at the 1970 New York auto show. The XP-882 had a tapering body with dramatic fender flares and a louvered rear window like the Mako Shark II concept car. Like so many midengine ‘Vettes before and after, GM brass decided to stick with the tried and true front-engine layout.
Also in the 1970s GM president Ed Cole — another legendary engineer who led the development of the small block V8 and catalytic converter, among other achievements — became enamored with the Wankel rotary engine. Duntov built two midengine experimental ‘Vettes with rotary engines, glad for Cole’s support despite not sharing his enthusiasm for the engine.
Sketching and notes about the Corvette, one of the many originals on display for workers to see at the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020 (Photo: Eric Seals, Detroit Free Press)
The 1973 Corvette 2-Rotor XP-987GT was a smaller, European-scale sports car with a rotary engine. The body was all Corvette, but its chassis came from a Porsche 914. Italian design house Pininfarina built its body. GM displayed the 2-Rotor at auto shows in Frankfurt and Paris before the car disappeared, probably sold to a collector.
Bill Mitchell’s most beautiful car
At the same time, Duntov wanted to develop a bigger midengine Corvette. He and Cole hadn’t been on speaking terms since Duntov refused an annual bonus he thought was insultingly small. They made up, at least in part because Duntov wanted a budget to develop what would become the Corvette 4-Rotor Aerovette, an iconic, gull wing design. Duntov believed it was the most beautiful vehicle GM design chief Bill Mitchell oversaw in a career that included the ’57 Chevy Bel Air and ’66 Buick Riviera.
Duntov recycled the XP-882’s chassis for the Aerovette, which featured silver leather interior trim.
A picture of the Aerovette featuring bi-fold gulping doors in the sports car that was never made. It is one of many photographs, drawings and sketches on display on all things Corvette design inside the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020 (Photo: Eric Seals, Detroit Free Press)
Despite the car’s striking appearance, Duntov would come to believe his agreement to use a rotary engine was a nail in the midengine ‘Vette’s coffin.
Despite that, another midengine engineering car arrived in 1974. The XP-895 began its life with a steel body. Intrigued by the idea of lightweight materials, DeLorean asked Reynolds Aluminum to create an aluminum body. That cut the car’s weight by nearly 40%, but DeLorean pulled the plug on the project because he wanted a smaller, more European design.
That never happened, and design work on midengine ‘Vettes came to a halt for more than a decade, as GM struggled meeting the challenge of higher fuel prices.
Closing the deal
By 1986, the quest for a midengine Corvette was ready to create another giant figure, and it got one when a young designer named Tom Peters began work on the Corvette Indy concept car. Peters went on to become the chief designer of the sixth- and seventh-generation C6 and C7 Corvettes and play a key role in starting work on the 2020 C8.
With a radically short hood compared to production ‘Vettes and cutting-edge technologies including four-wheel steering, traction control and active suspension, the Indy — so named because it used a 2.65L V8 Chevy developed for Indy Car racing — kept dreams of the midengine ‘Vette alive
The 1990 CERV III — this time the C stood for “Corporate,” not Chevrolet Engineering Research Vehicle — was the next step. Datini’s research convinced him it was an attempt at a production version of the Indy.
CERV III had scissors doors and was built of Kevlar, carbon fiber and aluminum. With a 650-hp twin-turbo 5.7L V8, GM predicted a top speed of 225 mph. It debuted at the 1990 North American International Auto Show in Detroit.
After that, work on the midengine Corvette went undercover for two decades. Photos of disguised prototypes at test tracks surfaced from time to time, but the car seemed to be as much myth as metal. There are whispers the Great Recession halted work on one, setting development back years.
A display of Zora Arkus-Duntov known as “The Godfather of the Corvette” at the General Motors Warren Technical Center in Warren, Michigan on Friday, January, 31, 2020. (Photo: Eric Seals, Detroit Free Press)
Development of the 2020 Corvette Stingray began around eight years ago, a long time for most projects, but the blink of an eye when it’s the last chapter of a 60-year story.
Mark Phelan for Detroit Free Press
Following Jeremy Welborn’s insightful post last week on Customer Ordered 2020 Corvette Production Starting, a reader left a comment about stopping by the Corvette Assembly Plant and seeing twenty-five C8 Corvettes in the parking lot. Thanks to Jeremy’s follow-up, Jay sent us some of his favorites that he took and gave us permission to share.
We’re calling this Corvette Heaven Part II as it seems to dovetail perfectly with yesterday’s blog post with an instagram video showing fifteen 2020 Corvettes lined up in a row.
From Jay Shellabarger:
I was at the Bowling Green Assembly Plant and Museum to see Shane for my Museum Delivery on Thursday, January 30th from 2:30pm to 4:30pm. I went directly to the Assembly Plant and looked at twenty-five C8 Corvettes in the parking lot and I took a hundred photos. I had been told all the pre-production cars would be smashed. I read where you state the VIN numbers are 5100001. Starting with 51 and all the cars I saw started with 50. I took photos of the VIN numbers too. I saw cars 5000028 (#28), 30, 56, 62, 124, 137, 138. 139 many up to number 5000375 (#375). I had a fun afternoon driving into the different parking lots (including employee parking lots) and looking at the C8’s produced. They are simply BADASS looking and I can’t wait to obtain my white C8.
Jay managed to capture nine of the twelve colors and several cars have full-length body stripes. We noticed that Jay also captured a Sebring Orange 2020 Corvette Stingray Coupe wearing thr 5VM Visible Carbon Fiber Aero Kit:1
Jay tells us he has an Arctic White C8 Coupe on order and he is customizing it with the High Wing and he also tells us he’ll be adding his own stripes to the car as well as chrome wheels! Sounds like a stunner, Jay!
Here’s the photos of the C8 Corvettes from the Bowling Green Assembly Plant last week:
Photos by Jay Shellabarger
There’s A New Engine In The C8.R Corvette, And It Sounds Nothing Like Its Predecessor.
They say beauty is in the eye of the beholder, and although that’s true, it can also be in the ear of the listener.
Since the Corvette first hit the streets back in the 1950s, it was imbued with the beautiful and nearly magical sound of V-8 performance. It was a deep, bass-filled rumble that just oozed a feeling of power. Over the years, the sound emanating from Corvettes, both on the street and at the track, had a distinctive note that became synonymous with the car. When the Corvette moved to the LS1 in 1997, the firing order was tweaked a bit, and although the sound did change, it still had that deep rumble that we all love.
But the only thing constant in the world is change. For the C8.R, Chevrolet Racing really changed things up with its new mid-engine marvel, but it wasn’t the engine placement that ended the car’s iconic sound signature. It was the engine itself. Gone is the deep baritone exhaust note, replaced instead with a high-pitched Ferrari-like sound. Think puberty in reverse. And although we love the sound of a wound-out Ferrari or other Italian supercars, having that pitch emanate from the back of a Corvette is something that will be hard to get used to. We’re not saying the sound is bad—it’s actually pretty badass—but it’s not even close to the sound signature we’ve come to associate with Corvettes.
The real culprit here isn’t the new 5.5L DOHC V-8 that Chevrolet moved to. Instead, it was the choice to go with a high-revving flat-plane crank. This drastically changed the firing order of the engine and eliminated the classic American V-8 sound that’s typical with the firing sequence of a traditional cross-plane crank. But we know what you’re thinking: “Well, this is just the race car, so I’m going to be able to get my V-8 rumble fix from the production car!” Well, yeah, for now. You see, for Chevrolet Racing to run this new DOHC flat-plane crank mill in the C8.R, it has to, according to the rules, run a similar engine in at least 300 production cars. So does this mean that an eventual C8 Z06 variant will lose its iconic exhaust note?
Forget Mustang vs. Camaro. Ford’s Shelby GT500 is ready to challenge Chevrolet’s flagship C8
Mustang vs. Corvette? Go ahead, pinch your thumb and index finger to the bridge of your nose, squint your eyes, and blink hard. When you look again, the words on the page won’t have changed.
Rarely has MotorTrend conducted (or concocted) such a bold comparison. But it’s a mad, mad new world we’re in now. Forget the Blue Oval’s sacrosanct rivalry with Camaro, which had always left the Corvette to chase the elusive, pricier Porsche 911.
Oh sure, the base pony car models will still compete, same as always. But the top-end Mustang GT500 is so excellent it deserves higher-octane competition. The final piece of evidence: The Mustang Shelby GT500 costs more than Chevrolet’s new mid-engine Corvette supercar when similarly equipped. Game on.
The C8 Corvette and Shelby GT500 have stirred up more buzz than anything else that’s come from the Motor City in recent memory. After decades of teases and concepts, the ‘Vette finally slides the engine back in the chassis to join the transaxle aft of the driver’s derriere. And after the extremely successful Shelby GT350, which finished a sharply creased second place in our 2019’s Best Driver’s Car, Ford brought in even heavier artillery with a load more horsepower and torque.
These two contenders offer different kinds of appeal, both inspiring great desire in the high-performance enthusiast world. Both offer capabilities that measure well against far pricier foreigners, without the kind of sacrifices that used to come with the label “Made in America.” Gone (mostly) are the long-muttered utterances about cheap features and fixtures, crude handling, and lack of refinement.
Of course, when you look inside these two cars, there’s an immediate difference. The Corvette is an American interpretation of a mid-six-figure European supercar; the Shelby has nearly the same interior as that rental Mustang convertible at the Hertz counter at LAX—albeit with better seats and some minor brightwork tacked on to disguise its cheesy rotary shift knob and plasticky switchgear. Ford’s interior guys still have some work to do before they can declare their Shelby variants to be world-class premium.
But this is not a comparison test for value shoppers who peruse our Buyer’s Guide, niggling over inches of legroom and warranty coverage.
This is a track test—the literal interpretation of where the rubber meets the road.
The C8 Corvette has come of age—finally, I might add—with a style and behavior that bring to mind a word like “sophistication.” The Corvette’s new shape will sit well with the German and Italian exotica in the valet lot at the country club.
The Shelby GT500 comes from another, more purely American place, the pony car. But since the arrival of the S550 chassis in 2015, the muscular Mustang and its more powerful derivatives have risen above the hot rods of yore, to compare well with European icons.
The ‘Vette excels with exotic appearance, precise and agile handling, and balanced power with a nice rush of strong, smooth, jetlike urge. The Muscle-tang crushes like a bodybuilder with brains. Its huge forward forces do not overwhelm its chassis, as in many of the beloved classics we’ve known before.
The C8 Stingray carries a lithe, striking new shape that will grab attention from a block away. Its lines do a terrific job of conveying more of a sense of value and beauty, yet it’s still imbued with a half-century-plus of genetic identifiers. I predict this car will generate more than a few “Oh, wow!” reactions from the public long after it has gone on sale.
The Mustang is a beefed-up beast with bulging biceps, based on our well-known sporty coupe. It will light up the pony car crowd, certainly. But among the elites, the Shelby’s familiar muscle-bound shape may still result in upturned noses, window-rattling V-8 rumble or not. Where the Mustang scores more points in this contest is in its competence in motion.
At speed, the ‘Vette’s strongest dynamic assets are described in a list of two: first, low polar moment, and second, forward traction. Chevy engineers have created a machine that benefits in exactly the ways it should: more centralized mass and the resulting rearward weight bias.
The Corvette has long been the bad boy of the racetrack, the Bart Simpson of supercars: rude, loud, cheap, unpredictable, and hard to handle, but fast and fun in its own brash way. Now, the Corvette has finally grown up. The C8 Corvette is more sophisticated, capable, and mature.
When the majority of the weight in a chassis is nearer the center of gravity, the car will change direction more eagerly. Formerly carried way up front under those arching fenders, the big engine actually resisted the steering tires as they tried to pull that hunk of metal around to face the apex of a turn. The amidships engine makes the steering feel responsive, more direct, and more precise. It’s less work. The new ‘Vette slices its way into a bend in a most delightful way.
Too much, sometimes—and this is the tricky part of the setup. Quick response can overwork the rear tires and create oversteer. In several high-speed tests, and again here at Virginia International Raceway, we have found some of that in the C8’s track personality. It really will point to the apex entering a corner and sometimes overdo it and end up sideways, with the widely adjustable stability control switch fully off (thank you for providing us with that choice, Chevy).
But when you apply your American V-8 torque, then you find the greatest improvement in driving the American Sports Car: It puts ponies to pavement. The C8 hooks up. Chevy has taken advantage of placing the engine over the rear wheels, and that loading successfully creates forward thrust far better than any Corvette before. The new ‘Vette launches hard from a slow corner or a stoplight/dragstrip. Check out that 0-60 time, beating cars with far higher power ratings and even some with all-wheel drive. That, my friends, is traction.
In fact, the ‘Vette transfers weight rearward so well that it sometimes goes into another kind of slide: understeer. The front loses grip a bit prematurely as a result of the light front loads. What to do? Is it bad? No, but this is a brand-new baby, and there’s still something to be learned. We believe we will see the C8 Corvette improve further as the Chevy team learns more about this all-new mid-engine phenomenon.
In street-tuned mode dashing around VIR, the ‘Vette revealed deliciously instant steering response. It was quick and stable as I carved into a corner, and it revealed snappy trailing-throttle oversteer when I released the brake. Both are clearly influences of the mid-engine low polar moment.
As I accelerated off slow corners, like VIR’s Oak Tree, the C8’s ground-gripping traction rockets the car forward, and it remains well balanced even though it feels like it might wheelie. I found a consistent gradual side slip in third and fourth gears exiting faster sweepers. The C8 has more power oversteer at 80 mph than it does at 40, which is unusual.
The new Corvette’s braking was strong and stable with moderate nose dive. There was some isolation, if not the degree of e-pedal numbness I feared, and the brakes were cooled with some really nice Z51 brake ducts. Last, there was no more float, better suspension damping, but not harsh.
Crawling under the hood, we then adjusted the C8’s suspension to its track settings—which simply comes down to much more negative camber, front and rear. When added to the 8 degrees of caster (the same in Street or Track mode), the Corvette creates camber gain when the wheels are turned, which is especially good for tight turns, and a strong self-centering force for stability and good on-center feel.
High caster will also cross-weight a chassis because the outside wheel swings in an arc upward as the inside wheel swings down. These will both typically work to reduce the understeer that we squawked about in earlier tests.
The effect of the added camber was much improved grip everywhere, reducing but not eliminating traits of midcorner understeer and drop-throttle oversteer and raising speeds with better manners. The basic traits of midcorner understeer and trailing-throttle oversteer were still there, just not as much.
In Track setup, the Corvette’s lap times improved by 2 to 3 seconds with less falloff and better grip on a long run. Tying this all together was an eight-speed dual-clutch transmission that worked quite well at full chat, completing the performance of a much improved product. Far more than deserving of the title, this fresh offering is a 21st century new chapter, with more room to improve. One step back with the engine is a giant leap forward for the Stingray.
The GT500, on the other hand, has sprung from the loins of another highly regarded thoroughbred, the GT350. As such it comes from a known source that has been developed for years. It shows on track, especially.
Whereas the C8 is precise, the GT500 hoons. Toss it around. Grab it by the scruff of the neck. This pony encourages aggression. Its version of refinement manifests in confidence for the driver. And the GT500 works in both standard and Carbon Fiber Track Pack form. It is beautifully balanced on track. The steering stays alive all the way through a corner. Quick turn-ins show no evil twitches. Pouring on the ponies rockets it down the straights, and slides come slow and controllably. Within reason.
There’s that word again: reason. Use it when you squeeze down the Shelby’s accelerator. The supercharged cross-plane Coyote-based V-8 clearly makes all of its advertised 760 horsepower. This is another step into the Brave New World of high technology, and overeagerness with that gas pedal will be rewarded with jail and/or hospital time.
Every one of those ponies made themselves known as the Mustang devoured the long back straight at VIR, touching nearly 170 mph, lap after lap. No power fade here, unlike some other American blown V-8s making similar numbers.
The Coyote belts out a stirring bellow or calms to quiet as a mouse with just a switch of the electronic valves in the dual exhaust, allowing you to decide whether to wake the neighbors.
All that thrust goes through a new Tremec dual-clutch seven-speed that exhibited fine behavior on the street and flat out. Manual shifting during a hot lap is just a distraction, and the GT500’s auto mode rivals Porsche’s PDK (yes, really) and does everything I would do, anyway. It even had the savvy to hold a higher gear in places rather than constantly throw out raucous downshifts.
On straights, there’s a rewarding “over-torque” feature that gives a little extra shove on each shift, like a manual power shift. Yet in corners, I felt the Tremec smooth those out. Impressive. The track program is really dialed in. The Ford team should be proud.
This thrust twists a trick carbon-fiber driveshaft into a Torsen gear-type limited-slip differential—a good choice for a front-engine chassis because it doesn’t lock up much off power. This helps get the GT500 pointed into the turn, and it’s also a non-wear item, unlike the clutch-type diffs.
If the driver remains very responsible with the right pedal, the Shelby is responsive and stable. The MagneRide shock system soaked up the curbs and bumps, but it floated a bit under the loads of pro speeds. Happily, though, when the PS4S tires did break loose, it was mostly a gradual, even enjoyable experience. The GT500 has that magic combination of steering response at the limit: the ability to tighten its line while loaded laterally in the middle of a corner, without losing grip at the back.
The Shelby handles this great grunt very well—even with its traction/stability control fully disengaged. (I don’t recommend this unless you’ve completed several professional driving schools, one of which Ford offers with the purchase of a GT500, or have won Daytona at least once.) It’s an incredible thrill, breathtaking, to lay the pedal to the metal. But it requires skill to handle that thrill.
Stopping this rig were perhaps the largest rotors (16.5 inches) and Brembo calipers I’ve yet to experience. Although the big Shelby could dive deep, deep into the tight corners VIR presents at the culmination of its long straights, it was here I could find my only real complaint: a bit of a long brake pedal, which was a little disconcerting at 170 mph. No fade but some squish. They even bled the brakes for me, yet both test Shelbys felt spongy. This was surprising because I recall complaining that the GT350’s brakes were too strong, requiring only a big toe. Perfect would be somewhere in between
The incredible performance capability of the new Shelby (especially with the Carbon Fiber Track package) moves the Mustang into the supercar realm, it pleases me to claim. Both Shelby models provide such thrills that they represent good value even at these prices—driving with confidence-inspiring and consistent speed that is rare to find at any price.
So, to the numbers: Lap times for the C8 Z51 and the standard GT500 were quite comparable, though achieved in different ways. The Shelby evaporates the straights; the C8 carves the corners.
The Shelby carries the load of your family, so in spite of its fantastic, predictable balance, the Corvette can leave it in the twisties, driven precisely.
Once we tried the GT500 equipped with the Carbon Fiber Track package, however, it was all over for the street ‘Vette. The CFTP Shelby is magic on the racetrack, wearing R-compound Sport Cup 2s, carbon wheels, lower and firmer springs/bars/shocks, a proper wing and hell-yes-they-work aero fitments, and much more. Fire it up, and the Shelby is long gone in a blaze of glory.
So here’s the greatest difference between these fantastical motorcars. Shelby: raging, proficient power. C8 Corvette: precision, potential, and style. The price, similar. The choice, yours. The pleasure, ecstatic.
Source; Randy Pobst: MotorTrend