The Big Engine That Did
By Connie Goudinoff Downing

In the past, the Mazda approach to racing in America had been to offer some support to several independent teams who then had to secure additional sponsorship to carry on. It had been an extremely successful strategy, resulting in numerous wins for many different Mazda models from RX-2s to Camel Lights cars. Thirty-seven IMSA drivers and/or manufacturers championships had been secured in various classes, and by the end of 1989, the RX-7 alone had recorded 96 wins.

When the 1990 season began, the Mazda racing program, now under the direction of Motorsports Manager, Dick St. Yves and part of the Mazda's Marketing Division, fully supported two factory teams and no independents. A GTU (Grand Touring Under 3-Liter) team, managed by longtime Mazda stalwart, Roger Mandeville, fielded two MX-6s for drivers Lance Stewart and John Finger. The two-car GTO team, funded directly by Mazda Japan, was to be managed by Jim Downing for Pete Halsmer and various other drivers.

IMSA's GTO division, in existence since 1978, was for production-based race cars, with engines exceeding three liters in displacement. IMSA used a sliding scale to relate weight to engine size to equalize competition. The intention was to produce high tech racing machines that looked similar to models seen in showrooms although the silhouette was the only part of the race car required to actually match production models.

By 1990, the series had become so competitive and so expensive that only factory backed entries had a chance of winning. The Mazdas were to compete against factory-backed Mercury Cougar XR7s, Nissan 300ZXs, a few independent Camaros, Fords, and an occasional Ferrari in what was to be a hotly contested season.

Mazda's new program had begun with the hiring of designer Lee Dykstra in 1989 to design a four-rotor RX-7 to IMSA GTO specifications. Indianapolis-based, Dykstra was well known in the professional racing world for his work with GTP, Can Am, Trans-Am and Indy cars.

Over the following year the components came together in a steel space frame chassis with aluminum and carbon fiber panels, composite bodywork, and the 26B rotary engine from Mazda Japan. (See 1990 car specs below). It was to be campaigned from Jim Downing's Downing/Atlanta race shop with team personnel from Downing's organization. Downing's rotary engine wizard Rick Engman, was dispatched to Japan to learn all the intricacies of the four-rotor engine.

1990 Car Specs for the GTO Mazda RX-7

Engine: Mazda 26B rotary (4-rotor) Displacement: 654cc x 4 = 261cc (160 cubic inches) Maximum Power: 600+ hp at 8500 rpm Maximum Torque: 390 lbs. - ft /7000 rpm Carburetion: EGI (Electronic Gasoline Injection)
Chassis: Steel space frame with aluminum and carbon fiber panels
Transmission: Hewland - 5-speed and reverse
Clutch: Triple plate (Borg & Beck)
Front Suspension: Double A-arm/inboard coil shock units with push rod
Rear Suspension: Double A-arm/high mount coil shock unit
Front Brakes: AP ventilated disc 6-piston caliper
Rear Brakes: AP ventilated disc 4-piston caliper
Shock Absorbers: Koni
Tires: Goodyear Front: 24.5 x 12.5 x 17 Rear: 27.0 x 14.5 x 17
Wheels: BBS 3-piece Dimensions and Weight:
Length 169.9 in. Width 79 in. Wheel Base 95.7 in. Front Track 64 in. Rear Track 62.25 in Weight 2,250 lbs

The team's debut was at the 1990 24 Hours of Daytona. St. Yves had succeeded in hiring defending GTO champion Pete Halsmer away from the Roush Lincoln/Mercury team to be the lead driver in the RX-7s, hence the #1 displayed on the hood of the car. The second car bore the #63, Jim Downing's traditional racing number. For that inaugural race, Halsmer was joined by John Morton and Mazda development driver, Elliott Forbes-Robinson, in the #1, while Downing, Amos Johnson, and John Osteen campaigned the #63.

Right out of the box, Halsmer qualified the #1 car on the GTO pole with a new track record to start 16th overall. The #63 qualified 19th. At the end of 24 hours and more than 2500 miles, the #1, after setting the fastest race lap, was parked, having suffered what was to be its only engine problem for the entire season. The #63, which Halsmer joined later in the race, finished second in GTO and seventh overall.

The independent RX-7 of Peter Uria, Bob Dotson, Rusty Scott, and Jim Pace, won the GTU class, scoring the RX-7's 97th IMSA victory.

At the second race in Miami, Halsmer finished second. At the following 12 Hours of Sebring both cars failed to finish due to mechanical problems and a crash during the race. Following that event, Jim Downing stepped out of the driver's seat to concentrate on managing the team and Elliott Forbes-Robinson drove the next few races. Near the end of the season, Lance Stewart was given a chance in the #63 while Price Cobb, who was to become the full time driver in 1991, drove in the final event.

Halsmer had his first victory at Topeka followed immediately by another win at Mid-Ohio. But the most important race of the season turned out to be in the streets of San Antonio, where Halsmer won his third race of the season and scored the Mazda RX-7's 100th win in IMSA competition. It was the culmination of a drive that had started in 1979 with the RX-7's first IMSA win at the 24 Hours of Daytona.

Pete Halsmer on the podium in San Antonio in 1990, celebrating the RX-7's 100th victory in IMSA competition.

Halsmer went on to finish third in the championship standings. Along the way he had recorded four starts from the pole and five fastest race laps as the new program, the team, and the new car developed into a formidable racing unit.

The four-rotor had proven reliable, with only one engine problem the entire season, while modifications had been made to the rest of the car after every event.

When the 1991 season started, the car had been tweaked and honed for a year and the development continued. As Dykstra described the GTO cars near the end of that season, "There are very few parts that are left (from the original car). The only part that's left is really the frame, because we've changed body panels. We've changed all the suspension, the brakes, the transmission, the suspension, geometry, all the coolers. There has been a lot of change."

And by the way, IMSA added 100 lbs to the RX-7 at mid-season.

The driver line-up for the 1991 season was solidified with Pete Halsmer in #62 and Price Cobb, 1990 LeMans winner, in #63. To say the season was hotly contested would be putting it mildly. The factory competition remained the same although the Ford factory cars were now racing as Mustangs. There were crashes, grudges, protests, and some very exciting racing.

Mazda RX-7 GTO cars at Daytona with team principals. Third from left, driver, Pete Halsmer; Mazda motorsports manager, Dick St. Yves; Designer, Lee Dykstra; Downing/Atlanta engine specialist, Rick Engman; eighth from left team manager, Jim Downing. At the far right is Mazda competition manager, Ken Kinoshita, fifth from right, driver, Price Cobb.

Halsmer had wins at Palm Beach, Miami, and Mosport while Cobb contributed wins at New Orleans and Laguna Seca giving Mazda the manufacturers championship in GTO. Halsmer clinched the drivers championship at the final race at Del Mar while Cobb finished third in the championship standings. In this highly competitive season Cobb and Halsmer between them, had toted up five wins, 27 top-five finishes, four poles, and seven fastest race laps.

With the addition of another RX-7 GTU win by a private entry at Daytona the venerable RX-7 now had scored 106 wins in IMSA competition.

By March of 1991, development had slowed on the GTO cars as time and budget were diverted to the upcoming GTP program. Near the end of the season St. Yves formally announced plans for 1992. There would be only one team, with two four-rotor prototypes, to compete in IMSA's top GTP class. The team would be a factory effort, housed in Charlotte and managed and campaigned completely by in-house personnel.

The two GTO cars were retired and factory support for the RX-7 ended. Both cars were shipped to Japan. In 1994, Japanese factory driver Yojiro Terada campaigned one of the RX-7s at the 24 Hours of LeMans with Frenchmen Franck Freon and Pierre de Thoisy co-driving. They finished 15th overall and second in a special IMSA GTS class. They went on to race the car again that year in a 1000 km race at Japan's Suzuka circuit where they led the race for a time, but were delayed by brake problems and finished 14th overall, but first in the IMSA GTS class. Following that season, the RX-7s were retired once again. One of the RX-7s remains at Mazda headquarters in Japan and is occasionally on display.

The car that scored the RX-7's 100th win was returned to the United States. It was recently refreshed in the shops of Downing/Atlanta and now resides at Mazda headquarters in Irvine, California. It most recently appeared at the Rolex Monterey Historic Automobile Races in August of this year, and at Mazda's annual Seven Stock event at Mazda headquarters in Irvine. More public appearances are planned for the car for next year.

Where are they now?

Pete Halsmer: Drove for the Mazda factory GTP effort in1992. Lives in Michigan and for the past few years has driven a Honda in the Grand Am Cup and Grand Am GT series.

Dick St. Yves: Managed the 1992 GTP effort. Now lives in Tennessee and works for Mazda as a district manager.

Lee Dykstra: Designed the 1992 RX-792P prototype GTP car. Currently serves as technical director for the Champ Car World Series.

Major contributors to the RX-7's 100 wins in IMSA competition.

A total of 38 different drivers contributed to the Mazda RX-7's 100 wins in IMSA competition. (Some events have had two to four drivers sharing one car).