When Eagle spread its wings
In 1972 All American Racers’ Eagle became the first Indycar to smash the 200mph barrier, a highlight in a record-breaking year for a great car
Indycar racing is always spectacular, but for many people the most dramatic era was the decade from 1963-73, when revolutions in tyre design, aerodynamics and turbocharging resulted in giant performance leaps – and finally that awesome milestone, the first 200mph lap.
After the serious arrival of the rear-engined car at Indianapolis in 1963 with Lotus, the track record at the big speedway went from 150mph in 1962 to 160mph in ’65, 171mph in ’68, and then 179mph in 1971. But the great god aerodynamics began to make itself known, presaging an even more impressive jump in speeds in 1972. In theory, wings had been banned by USAC in 1969 but the old club left a loophole by permitting wings if they were incorporated into the bodywork. So everyone began building huge, shelf-like engine covers that were thinly disguised wings.
McLaren’s 1971 Indycar, the chisel-nosed M16, took this to the maximum with a huge tail wing incorporated into the overall wedge-shaped design. Driven by Peter Revson the McLaren increased the track record at Indianapolis by 8mph, three quicker than Bobby Unser’s ’71 AAR Eagle. By May of that year it was clear the new aerodynamic age had arrived in open-wheel racing. The M16 was a quantum leap and it made everything else obsolete.
Rather than clamping down on the aerodynamic genie, USAC permitted free-standing wings for the 1972 season as long as they weren’t moveable or attached to the suspension. Also, tail wings could extend the full width of the car to the outer edge of each rear tyre, so the wings became massive, more than 5ft wide. All American Racers followed McLaren’s lead and hung its rear wing as far back as the rules allowed.
“We didn’t know for sure what was right or wrong, but we had the McLarens to use as a guideline,” says Unser. “No matter what, we were all dumb – Dan [Gurney, top right], the designers, and me too. But I kept watching the McLarens and looking at that big wing acting as a lever back there.”
Roman Slobodynskyj led the design team for the ’72 Eagle, which would become a classic Indycar. They equipped it with twin side-mounted radiators, like the M16 McLaren, rather than a single nose-mounted radiator, so the nose was free to assume a chisel shape between a pair of big front wings.
A huge rear wing, its trailing edge 42in behind the rear wheel centreline, made for maximum aerodynamic leverage.
“It was a terrific car,” says Gurney. “It took our breath away. It was a tremendous accomplishment and we were very proud of it. Roman deserved a lot of credit. Not the easiest guy in the world to work with but we tried to give him free rein. When you look at the centre of gravity and the need for good cooling in and out, it was exceptional. We did make models of it for a wind tunnel but it was more eye-balling it than anything. But it was a neat package.”
A key component in making the ’72 Eagle work so well was Dan’s invention of the ‘Gurney flap’ while they were testing at Phoenix that winter. He thought of and hammered out his first Gurney flap right there in the garage while Unser was testing. Dan then attached his creation to the trailing edge of the rear wing. “Honest to God,” says Unser. “I hadn’t made half a lap and I already knew we had made the biggest discovery in the history of motor racing!”
Unser pulled in and asked Gurney to make a couple of similar flaps for the front wings to balance the effect. When he went out again he found the car really stuck to the ground and he could drive it much deeper into the corners.
Meanwhile engine man John Miller found a jump in power to match. Collaborating with Garrett AiResearch on a big turbocharger Miller’s horsepower numbers went through the roof, with more than 1000bhp available for qualifying.
With the car ready to race a serious intramural contest erupted between Unser and new team-mate Jerry Grant, Gurney’s old friend and long-time team-mate going back to the formative days of Dan Gurney Racing in 1963 and ’64. “I never did like having a team-mate,” says Unser. “But I was always straight with them. Everything I did during my testing and development work went out the proper way. Every item was done by myself and the guys who made the stuff. Then Dan gave it all to Jerry. That really, really pissed me off.”
Grant hung out persistently in front of AAR’s garages in Gasoline Alley before finally getting the ride in the team’s second car at Indianapolis in 1972. “That was a movie in itself,” he grins. “Bobby didn’t want me. He wanted a sprint car driver and Dan wanted me. I sat outside the garage every night on a wheel horse and they made the deal with Bobby on the Friday night that if Grant was out there when they left then he got the ride. And I was there of course, and got the ride.
“Through my Indy career with Dan he always favoured me personally over Bobby Unser. But I continually got the second-grade stuff. Bobby had the choice of engine and did all the testing so I had to come in stone cold. But I became quite a rival.”
Grant was a serious threat to Unser on the high-speed tracks. “Bobby was scared of me on a superspeedway,” says Grant. “He wasn’t concerned on a mile [track] because I never got the chassis set-up right to run the mile. Dan was always working on my chassis; sometimes we had the best car on the race track, and that was because of Dan. I could tell what the car was doing and he was never afraid to make big changes.”
The competitive situation between Unser and Grant created a deepening schism. “The whole team started picking sides and conniving,” admits Unser.
Despite growing internal dissension, All American Racers was ready for the new season. In the 1972 season-opener at Phoenix, running as AAR’s lone entry, Unser qualified on pole, beating the next man by 4mph, and he won going away – a prelude to a truly remarkable season for Unser and AAR. As soon as practice began at Indianapolis in May it became clear that the latest Eagle was going to rewrite the Speedway’s record book. In the end Unser qualified comfortably on pole, breaking the previous year’s track record by 17mph, the largest margin in history. He beat Peter Revson’s factory McLaren by 3mph and Mark Donohue’s Penske McLaren by 4mph. Most of the field was 10 or more miles per hour off Bobby’s pace. Grant qualified 15th.
Unser took control of the race in the opening laps only to drop out after just 31 laps because of a burned piston. With Unser out, Gary Bettenhausen took over in Penske’s second McLaren pursued by Grant in the second AAR ‘Mystery’ Eagle and Donohue. Bettenhausen was looking a likely winner but with only 18 laps to go his ignition system quit, handing the lead to Grant.
“That car handled so well,” recalls Grant. “We ran on race horsepower but Penske and Donohue and Bettenhausen had adjustable horsepower, so every time I closed on Gary he could squirt away from me. But he broke and I lapped Donohue before the last pitstop.”
Grant made his final stop for fuel after 166 laps but, with the race apparently in the bag, he surprised everyone by coming in again. A front wheel had gone out of balance and the vibration started to bother Grant.
“The problem was they had slowed me down so much because I had such a lead,” explains Grant, “and my tyre picked up a bunch of crap. Bobby was out of the race, so unexpectedly they pulled me into his pit. At the same time John Miller plugged in the fuel from Bobby’s tank. They yanked it out right away but we were hooked up for 1.2 seconds or something. That was the violation they got us for.”
As Donohue won for Penske and McLaren, Grant finished second but wasn’t credited with any of his final 12 laps after the illegal refuelling. He was classified 12th, and to this day remains unhappy with the spot ruling of USAC’s chief steward Harlan Fengler.
“It had been a $500 fine in the past,” says Grant. “We went to court on it but it was a waste of time.”
In June and July, Unser took successive poles for AAR at Milwaukee, Michigan and Pocono. He won at Milwaukee but dropped out because of engine failures at Michigan and Pocono. At Milwaukee’s second race of the season in August, Bobby took his seventh pole in a row, again obliterating the record. But USAC officials claimed there was a timing error and gave the pole to Mario Andretti instead, so Gurney told the team to load up and drive home rather than race.
Next was the California 500 at the new Ontario Motor Speedway. It didn’t take long to realise that on the recently opened new superspeedways the new Eagle was probably capable of breaking the 200mph barrier, unthinkable just a few years earlier. Sure enough both Grant and then Unser lapped Ontario at over 200mph in practice. Bobby was not at all happy that Grant was the first to achieve that benchmark speed.
“Dan wanted to go 200mph,” recalls Grant. “They were selling cars like hot cakes but there was a lot of competition from McLaren in particular. We had big blowers and I think Parnelli and Penske had them too. They ran as much boost as the blower would put out and Bobby blew up three engines. Finally, I was in line and Dan said, ‘Do you want to try to run 200?’ I’d been running 196 with race horsepower and I said, ‘Sure.’
“John Miller, the engine man, came up and said, ‘I gave it some more horsepower. Do you think you can handle even more?’ Well, that’s like asking a drunk if he wants another drink. So I said, ‘Sure!’ And then just before we fired up the engine Miller said, ‘You want all she’s got?’ And of course I said, ‘Sure!’
“When I went out I knew I had a lot of horsepower but I didn’t know how much. I short-shifted so I didn’t light the tyres, but it still lit them up in second and third gears. When I got up to speed I thought I had a top fuel dragster behind me! I thought I was going to go 220.”
Grant was sideways in all the corners on three of his four qualifying laps. “People said it looked like a smooth ride from outside but I was sideways and catching it every lap. Those cars you could drive sideways. Nowadays it’s like feathering a light switch but back then you could actually dirt-track the car. On the last lap when I knew I’d gone 200 I backed out of it and just brought it around.”
Grant’s first three laps were all over 200mph and he took pole just shy of the magic mark, averaging 199.600mph. The next day Unser turned the first official four-lap qualifying run over 200mph, at 201.374mph. He was a ‘second day’ qualifier, however, starting 23rd. But Grant’s engine blew on the pace lap and Unser came through to lead for a few laps before trailing into the pits, his engine blown as well. Clearly, at high boost, they were asking too much from the venerable Offy.
“We were really dragging a lot out of that old engine,” says Unser, “but it loved rpm. We were turning 10,500rpm, but the problem was the reciprocating weight of those big old Offy pistons. The rods couldn’t stand it.”
Unser won the year’s last two races, but was a distant eighth in the championship because of his poor finishing record in the points-rich 500-mile races. Nevertheless, Unser and AAR’s Olsonite Eagle were the unrivalled stars of the 1972 USAC season.
“That was a red-hot team,” says Unser. “We had a lot of disagreements but as a team, goddam, we made a good one! We knew how to find speed. They had a hell of a monkey in Bobby Unser and we tried many, many things. There wasn’t anything Dan wouldn’t try. Nobody raced any harder than he did. He was the best at making pit decisions and understanding what everybody else was doing. Dan knew how to call a race. He didn’t gamble like Roger Penske sometimes would. Dan was the best asset I could ever have. Even when I was really mad at him, I’d have never traded him for anyone else.”
AAR built 42 of the 1972-type Eagles, some for its own use, but most for numerous customers. It was the mainstay of Indycar racing through to 1976, often providing half the field. Eagle-Offy turbos won 26 USAC races between 1972-76 and Unser won the 1974 USAC title and the ’75 Indy 500 aboard AAR Eagles.
The 1972 Eagle did more than smash the Indycar 200mph barrier. It rewrote the record book like few other cars in racing history.