Record Run Retrospective at the Gathering

[Hib Halverson]

To commemorate the 25th Anniversary of the ZR-1 World Record Run of 1990, on Saturday of the Gathering, the National Corvette Museum will present the "Record Run Retrospective".

The "RRR" will be a panel discussion with audience participation about the Record Run. Panelists will be John Heinricy, WRR Lead Driver; Jim Minneker, WRR Driver; Don Knowles, WRR Driver; Ralph Kramer, former Director of Chevrolet Public Relations and Graham Behan, former LT5 Development Engineer at Lotus. Once again, I'm honored to have been selected by the NCM to be the moderator of the Record Run Retrospective.

For this WRR 25-th Anniversary event, the Museum is going to remove the Record Run car from its long-time exhibit in the motorsports area of the Museum to the Conference Center for display during the panel discussion.

Also, for this 25-th Anniversary Retrospective discussion I'm going to accept some questions in advance from members of the ZR-1 Net Registry forum.

There are two rules for these questions:
1) The subject of each question must relate directly to the World Record Run
2) Your real name, not your screen name, and your hometown and State must be attached to the question.

I'll pick the five best questions and ask them of the panelists during the Record Run Retrospective.

Please submit your questions by email to finspeed@netmotive.net.

Lastly, to get everyone's "creative juices" flowing in advance of the Record Run Retrospective, I've decided to post an early draft of an article which, in edited form along with additional content to be added later, will appear in Corvette Magazine this Fall.

Enjoy!

A Most Demanding Day
The Story of the ZR1 24-Hour Record Run
by Hib Halverson

Speed records–every motorsport has them. The unlimited Land Speed Record is 760.343-mph, set by Andy Green in 1997 driving a turbojet powered car at Black Rock Lake, Nevada. Speed in the quarter mile is 332.02-mph, set by Larry Dixon in 2012 driving a Top Fuel Dragster at Willowbank, Australia. The Closed Course Record, is 257.123-mph, set in 1987 by A.J Foyt in the Olds Aerotech LT at Ft. Stockton, Texas.

All those records have been hotly contested in last 100 years or so. The LSR has been held by more than 25 different cars, the 1/4-mile record by well over a hundred dragsters and the Closed Course by 17 different cars just since 1970.

So, what speed record is the most difficult to set?

By far, it's the record for average speed over 24 hours. There have been only seven attempts to set it since automobiles were invented in the late 1800s and only four were successful. Three vehicles have been used. Two of them were purpose-built cars. Only one was production-based–a Chevrolet Corvette.

Not So World-Class
The crop of "Z-models" in the last quarter century has kept Corvette at top the list of "world-class", performance sports cars, but for most of the 62 years the car has been in production, it hasn't been that way.

Before the C4 ZR-1 debuted 25 years ago, the Vette's performance fell short of world-class. In fact, during the late-70s/early-'80s car car was a slug. Going back to the 1950s, the car had a reputation for too much weight, lousy brakes and marginal handling.

A new platform in 1984, port injection and more power in 1985 and ABS in 1986 earned the Corvette some respect, but it still couldn't compete with benchmark cars in the "high-sports" market segment. Chief Engineer, Dave McLellan, and his development team knew they'd better do something about that if Corvette was to be king of the hill in high-sports.

March 1989: the 1990 ZR-1, known during development as the "King of the Hill Corvette", makes a spectacular public debut at the Geneva Auto Show. The combination of C4's already good suspension along with ride-adaptive shocks, a six-speed and the stunning 375-hp, four-cam, 32-valve, LT5 V8, produced ride-and-handing, acceleration and the 180-mph top speed that, finally, put the car right in the forefront of world-class. Add Chevrolet's masterful public relations and marketing and the ZR-1's impact on Corvette's reputation was huge.

Part of the promotion was the March 1990 "World Record Run" when a ZR-1 broke three Land Speed Records, including the 24-hour mark, which had stood for nearly 50 years.

The Idea
Summer, 1989. One afternoon, California PR consultant, Pete Mills, intrigued with the 24-hr. speed record, was talking with friend and professional road racer, Stu Hayner. Mills told Hayner that the record had been set in July, 1940 on a 10-mile circle at Bonneville by David Abbott Jenkins driving a purpose-built car named “Mormon Meteor III.

"Ab" Jenkins, a steely racer of the day known for his speed records, took his car to Bonneville the first time in July 1939. Jenkins was on course for 3 hours at 171 mph when the car caught fire. Just a few weeks later, still recovering from his burns, he went back to set the 12-hour endurance record. Not only did Jenkins survive a fire, but he did all the driving himself. The dude was seriously hardcore, an apparent requirement for setting endurance speed records. A year later, Ab Jenkins was at Bonneville, again, this time setting the 24-hr record at 161.180-mph. That mark would last almost half a century and, by 1990, was the only only significant pre-World War II speed record still standing.

Not for lack of trying. Three times major manufacturers tried to set the "24"–Ford (1969), Mercedes (1976) and Audi (1988)–but all failed. Mills went on to tell Hayner that an IMSA GTP road race team which ran Porsches told him that the fabled 962 (two LeMans wins, '85-'86 World Sports Car and '85-'88 IMSA GTP Championships) lacked the reliability to beat the 50-year-old mark.

Hayner had recently driven a pre-production ZR-1 in a speed test for Road&Track: Corvette, an annual R&T did back then, and knew the car's potential, so he suggested the ZR-1. Mills scoffed at the idea of a stock Corvette setting that record until Stu told how he drove one of the pre-production '89 ZR-1s 183 mph on a four-mile course near the California desert town of Yermo.

Hayner and John Heinricy drove Corvettes and Camaros for road race team owner, Tommy Morrison, and a few weeks later, on the way to a race in Canada, they cooked-up a plan to break the record. Heinricy, then Corvette/Camaro Product Engineering Manager, was enthusiastic. “Probably the main reason people buy the car is its image, particularly its racing heritage," he told Corvette Magazine. "I liked to do things to promote its image–the Corvette mystique. World Records are just another reason to want a Corvette."

When John Heinricy approached his boss, Dave McLellan, with the idea, McLellan was, as John recalled, "...real interested. I don't remember it going higher than McLellan. We just decided to do it. If we'd have gone higher, they'da just said, 'No.' Then, I talked to Doug Robinson (Development Manager) and got a couple of test cars and Jim Minneker (Powertrain Manager) about what powertrain might work. Jim was also one of the drivers."

Tommy Morrison supplied the substantial resources of Morrison Engineering and Development and his major sponsors, Mobil Oil. Hayner brought his sponsors: GM’s EDS Division, the Southern California Chevrolet Dealers Association and Goodyear. For drivers, besides Hayner, Heinricy and Minneker, there were: another Morrison regular, Don Knowles; Corvette's ride-and-handling wizard, Scott Allman; Showroom Stock racers Scott Lagasse and Kim Baker; along with Morrison, himself, making a team of eight.

Few North American tracks were suitable. The circular course at Bonneville, used by Jenkins 50 years before, no longer existed. They considered: NASCAR superspeedways at Daytona and Talladega (too expensive and their high banks loaded the car excessively), a Nissan track in Arizona (Nissan was unwilling) and the five-mile asphalt circle at GM's Desert Proving Ground (management had safety concerns). The "WRR" team settled on the 7.712-mile, low-banked oval at Firestone's Tire Proving Ground at Fort Stockton, Texas, site of Foyt's Closed Course Record in 1987 and Audi's unsuccessful 1988 attempt. While it could accommodate the speed, seven-degree banking, no guardrails, retaining walls or lights and an abundance of wildlife (cattle, deer, antelope, javelina and coyotes) in the area made the track treacherous at the 188-192 mph speeds they would run down the straights and 170-190 in turns.

“We came down here for one purpose…to set a new World Record," Stu Hayner said just prior to the event. "We knew going in it wasn’t going to be easy. No one sets records without taking chances."

The Cars
Two Corvettes, the ZR-1 and an L98 Coupe used by GM-Europe to set other records, were built and tested during late-'89/early-'90. This included a test at Ft. Stockton in November, 1989.

The Mobil/EDS/SoCal Chevy Dealers/Goodyear ZR-1 had a few performance modifications but many changes to insure reliability/durability and safety. A roll cage and other safety equipment were already in the car from its earlier use as a high-speed development vehicle. A telemetry system replaced the passenger seat so the crew could monitor vehicle parameters in real time. Additional instrumentation and switches for electrical accessories and a 48-gallon fuel cell were installed. As FIA rules require “non-consumable” spare parts (brake rotor, radiator hose, alternator, etc.) to be carried in the car, 300 lbs. of spares were in two suitcases lashed to the cages’ rear tubes. Replacements had to come from this stock and, if a failure was such that a car could not get back to the pits; the driver, working alone, had to fix the car.

The production suspension had only two modifications: 1) Goodyear Racing Eagle tires. Goodyear spent $250,000, a incredible sum of money back then, to develop a special 17-inch, radial race tire just for the Record Run and 2) removal of the rear antiroll bar to make room for the fuel cell and to optimize the car's handing with increased weight on the rear wheels, race tires, 190-mph corner entry speeds and 0.5-g cornering loads.

The exterior was stock except for: no side mirrors, lowered front end and an enlarged, reinforced front air dam fitted with ultrasonic “anti-animal” whistles. Racing lights were installed in fog light and turn signal mounts and two aircraft landing lights went in the front license plate housing.

The LT5 was straight from Mercruiser's Stillwater, Oklahoma assembly line. Greg Van Deventer, former member of Mercruiser's LT5 engineering team states "That engine was stock. It wasn't shipped because it had a minor balance problem. When the Record Run came up and they were looking for a motor, we gave it to Morrison."

With headers, open exhaust and engine controls calibration revised for racing gasoline, the engine made 405-hp. Tests showed the 190 mph necessary to reset the "24" came at 5500 rpm in fifth, so the gas pedal had a stop at 70% throttle. A set of tall, 3.07 gears replaced the stock 3.54s and the car was fitted with transmission and rear axle coolers.

"We did everything we could to mitigate risk, " John Heinricy recalled us. "We calculated the g levels we'd be running. Calculated the tire loads, then gave that to Goodyear and made sure they were comfortable with those loads. They ran tests on the tires. They X-rayed every tire. We had lots of time on that particular car. There was really nothing to break as the car wasn't that stressed. The engine was run hard, but not as hard as we ran them on the dynamometer during development."

Run Begins
The WRR Team returned to Ft. Stockton in late February. Present were: the drivers; Crew Chief, Tommy Roe and the Morrison Development team; GM engineers and technicians; a Goodyear contingent; sponsor and PR reps and, most importantly; officials of the United States Auto Club which sanctions Federation Internationale de l'Automobile (FIA) record attempts in the United States. After a week or so of preparation and a two-day delay for a winter storm, they were ready.

On 1 March, 1990, it was 35°, windy and overcast as John Heinricy rolled onto the TPG oval for a warm-up lap and, the next time by start/finish, at 9:55:12 AM Central Standard Time, USAC's clocks started on Corvette's attempt to reset the 24 Hour World Land Speed Record.

"Depending on wind," Heinricy told us, "speed was in the low 190s. We didn't lift in the turns. We entered them foot on the floor and by the time we came out of it–still at wide-open throttle–we'd be in the high-170s. It didn't slow down much in the turns.

"Getting through the first pit stop was important. I felt a lot better when that car left after my stint.”

The Run continued smoothly. About every 80 minutes, the cars came in. It took about 45-seconds to a minute to fill the 48-gal. tank, switch drivers, put on new Goodyears and clean the windshield.

By 3:56 p.m., the L98 powered car had set five FIA Category A, Group II, Class 10 records, including six hours at 170.887 mph. The car was withdrawn, certified by USAC, then trucked to Dallas where it was airfreighted to Switzerland for GM Europe to display at the Geneva Auto Show.

The ZR-1 continued on its appointed, 190-mph duties. By late afternoon, after eight hours, there was less worry about the car's reliability. The powertrain was running well. The chassis and tires weren't taxed that much by the low cornering loads. Fuel mileage was as predicted.

There were weather concerns. Don Knowles, in his afternoon stint, not only had 25-mph wind gusts but ran through intermittent drizzle and snow flurries. Think about that: driving 190-mph in light rain or snow...on slick race tires...with occasional cross winds.

Other of the Team's fears were things biological rather than mechanical. Hit a cow or a deer at near 200, the result would be instant death. Seven pairs of men, in trucks spaced about a mile apart on the outside of the track, scared off the big animals with shotgun blasts in the air but coyotes were small enough to slip by unseen. While they weigh only 35-40-lbs, hitting one could be catastrophic and it almost happened around sundown.

Hayner was running 180-plus through Turn Four when he saw a chilling sight. "A little speck on the outside edge of the track," Stu recalls. "It was a coyote and I had no chance whatsoever to brake. I decided to hit it and suffer the consequences rather than run off the track at near 200 trying to avoid it. I didn't lift–figuring it wouldn't make any difference. He came 10 or 15 feet down the banking. When I got 100 yards away, he heard the car. He stopped. I missed him by a few inches. This all happened in, like...two seconds."

Birds were a danger, too. An encounter with a Corvette at 190 was over quick as you can say "splat." Hayner told us, "I was out of the car and watching. I heard the radio, 'There's a great big bird on the track.' The car was coming and this bird, just–poof! At 200 miles an hour, they vaporize. We went out on the track and couldn't find anything but a few feathers."

The real fear was a bird coming through the windshield. Fortunately, the ZR-1's glass was tough. "Usually, you didn't even see the birds,"John Heinricy added. "They'd just go 'Bang!' on the windshield. I hit two or three. Other guys hit them, too. Occasionally, we came in with one stuck in the front end."

Things Going Bump in the Night
There was no moon on March 1st. "The late night stuff was scary." Scott Allman told us, "It was so dark, you couldn't see past the edge of the track. We had lights at the entrance and exits of both turns, so when you exited one turn, you could identify the next turn, but, except for the lights on the car, the straights were completely invisible. If some critter ran in front of you, you'd have no warning. We lapped at 190-mph–280 feet-per-second. The field of vision at night allowed less than a tenth of a second visibility before you'd hit an object in your path. I calculated that based on a coyote entering the track perpendicular to the path of the vehicle. Not a comforting thought, since it takes long than that just to recognize an event that requires a motor response."

Before the Run, there was a meeting with the Ft. Stockton Volunteer Fire Department. "I remember that like it was yesterday," Stu Hayner recalled, "We were thinking it was just another track–another race. Any time I'd been racing, if anything happened, by the time I came to a stop, safety crews were on the way. Somehow, we lost the idea that wasn't possible at Ft. Stockton.

"Heinricy had calculations," Stu continued, "which said, if we went off the outside of a turn, we'd fly such and such a distance (actually, it was 375-ft) before hitting the ground. That was a reality check, too. Then, they talked about big boulders out there along with all the animals. No guardrails? I figured there was less to hit. I was still pretty young, then. I think some of us were thinking: it won't happen to us. That's the mentality of most race drivers."

The Fire Chief was asked how long it would take to get to the car if there was an incident. He replied, "It depends if you're on fire or not." According to Hayner, the Chief's wry humor drove home the idea, "If you weren't on fire, he might not find you until morning–it was that dark–and if you were on fire, it still take be, maybe, 20-minutes to get there because the facility was so big and you'd be on rough ground far from the track."

Thankfully, no one went off the track, but besides the dread of that, there were other nighttime "experiences" which creeped-out drivers. "One thing that sticks in my mind is fog," John Heinricy told us. "Several times that night, I hit fog. It was really scary because the fog was in patches. I'd suddenly see it in the lights and then it would break over the windshield almost instantly. Luckily, it wouldn't last for any length of time. If it had been a big patch of fog, I'd have been in serious trouble."

Through the long night, the LT5 never missed a beat and the rest of the car's systems generally performed well. Lap after lap, lights boring a hole in the dark, the ZR-1 ran 190 down the straights and into the corners and 170-175 exiting turns. The Team's calculations had them comfortably over the 166-mph average required to break the record. Like clockwork, about every hour-and-a-half, the car pitted. If the run continued this way, the 5000 kilometer, the 24 and the 5000 mile would all have fallen by early the next afternoon.

One of the car's two mechanical problems happened at night. "On a night stint," Jim Minneker explained, "I got in and had a vibration right away. We were using the stock, low tire pressure warning system which had a five ounce sensor and a counterweight held on each wheel with a strap which broke, so I had ten ounces of imbalance bouncing around in the left front tire. I got to 120-125, it started really shaking–so bad, it broke my radio's microphone wire. I couldn't accelerate past that because the vibration got worse.

"The guys could tell by looking at vehicle speed in the telemetry. I could hear, but couldn't talk, so they told me to blip the gas once for 'Yes' and twice for 'No.' They asked if something was wrong. I gave them one blip. 'Do you know what it is?' One blip. We played 20 questions until they asked, 'Tire going down?' One blip. I made it around and came back in. They had front tires ready to go and I went back out."

Three Records Set
Friday morning, 3:36:06 AM, local, 2 March 1990. In-spite of drizzle, snow, wind, coyotes, bird strikes, fog and vibration, the ZR-1 set a new, 5000 kilometer World Record.

Dawn brought less stress and clear weather. The car was still running well. At 9:55:12 AM, the 24-hour World Land Speed Record, which withstood a half-century of assaults by other manufacturers, fell to a near-stock, overweight, Corvette ZR-1. Fittingly, Team Leader, Tommy Morrison was in the car at the time. Everyone was ecstatic when USAC said they'd beat the old mark by 14.7 mph, way more than the required 3%.

“To me," Morrison said after getting out of the car, "this was a very sacred thing we set out to do–break a record that‘s 50 years old. It was very difficult to achieve, but I’ve owned Corvettes since 1962 and there’s nothing I wanted to do more than break this record.”

The ZR-1 continued with the 5000-mile in reach but, incredibly, with eight laps to go, there was a problem–a coolant leak from a hose chaffed by the fan shroud.

“I figured we were sunk. Telemetry told us the coolant temp was sky-high. Even though, I knew we already had the (24-hr) record," Heinricy recalled, "my first emotion was a huge let down. We’d worked so hard to go down now.”

The car came in with the water temperature pegged. The crew replaced the hose and added coolant. Stu Hayner, the final driver, was told to run the last laps at 140 mph. The ZR-1 passed 5000 miles at 28-hours, 46-minutes and 12.426 seconds after the start.

Apparently, overheating didn't affect the LT5 that much as, Hayner unscrewed the throttle stop for two victory laps at full throttle. That’s 15 miles at almost 220 down the straights and 190 in the turn after 5000 miles averaging over 170 and then overheating.

The score? Three outright World Records: 5000-kilometers at 175.710 mph, 24-hours at 175.885 and 5000-miles at 173.791, plus four other FIA International marks in class A-G2-C10. Immediately after the event, the drivers and crew signed the underside of the hood. The WRR ZR-1 went on a promotional tour and then was donated to the National Corvette Museum where it remains, today.

"It didn't seem much of a deal until after I did it," Heinricy reflected. "I thought: 'Wow. This is a World's speed record–three speed records! And two of them stood for 50 years. Pretty incredible. What made me feel even better was that the car was so stock."

The ZR-1's Record stood for 11 1/2 years. It was reset at 183.45-mph in October, 2001 by Volkwagen's exotic, 600-hp, "W12 Coupe" prototype. A further-developed version of the same concept car reset the mark in February of 2002 at 200.67-mph, where the record stands today.

The Corvette remains the only production vehicle to ever hold the 24-hour speed record.


So...if you want your question asked of the Record Run panel, email it to finspeed@netmotive.net. I'll pick the best five questions and ask them of the panelists.

[Franke]

Hib, this is a fantastic prelim article. So much history right here. Thanks so much for sharing this knowledge/info with us. Kinda makes one proud to own such a incredible car.

[efnfast]

Cool read, glad I'm going to BG to hear the rest of the story.

[Hib Halverson]

Glad you guys liked the article. Hope to see both of you in BG in about ten days.

[XfireZ51]

Sorry I won't be there for this. Great story. If I were, I would ask "what specifically about the LT-5s performance gave Hayner the confidence to think it could do this?" As he drove the car during the R&T performance driving, I'd be interested in hearing his story during that ride that led to his sense the LT-5 could do the 24hours?
One other thing. Anyway we could record this so those of us not there could watch on YouTube or something like that?

[Hib Halverson]

Originally Posted by XfireZ51

Sorry I won't be there for this. Great story. If I were, I would ask "what specifically about the LT-5s performance gave Hayner the confidence to think it could do this?" As he drove the car during the R&T performance driving, I'd be interested in hearing his story during that ride that led to his sense the LT-5 could do the 24hours?

I've known Stu Hayner since the mid-80s. In fact, I was the one who obtained Stu's services for the "speed run". I was, also, present on that back road near Yermo CA, covering it for Road &Track's "Specials" division which used to publish a Corvette Annual. Hayner and two guys from the magazine testing staff who had the radar gun and a handitalkie and me shooting photos. I forget the actual speed, but it was right around 180.

Several months later, when Stu spoke to Pete Mills, the discussion was only about the car's speed potential and not its reliability/durability in a 24-hour record attempt. My understanding is that it was the GM guys (Heinricy and Minneker) who felt the durability would be there as long as the engine was throttle stopped.

In any event, that's a good question. Unfortunately, Hayner is not going to attend so only half the question can be answered.

One other thing. Anyway we could record this so those of us not there could watch on YouTube or something like that?

That's up to the Museum. I suppose if enough people ask, maybe they will tape it.

[diamond zr1]

as this was such a difficult complex project,done before the modern computer simulations it was a huge achievement.The fact that no large production run car has accomplished the feat since shows the effort involved. I do hope the museum films the interview,and makes it available,as well/As it is the 25 year of the zr1 makes it all the more special.

[Hib Halverson]

Other than the C4 ZR1 no "production run car" of any type has held that record. All the others were either purpose built vehicles or single-build prototype/concept cars.

[Dynomite]

That is some great writing and great history right there Hib
Thanks

[Hib Halverson]

To all who attended the Record Run Retrospective...thanks for coming.

All the panelists enjoyed the audience support.