The early 1980s was an exciting time for motorsports, especially due to the introduction of the new FISA-sanctioned Group C and the IMSA GTP regulations. Group C cars were eligible to contest for the World Championship with such prestigious venues as the 24 Hours of Le Mans. The GTP regulations, though similar to the Group C category, were endurance races in the United States. The purpose of having two similar categories but sanctioned under different governing bodies was to create a more level field of cars and to dismantle Porsche's dominance in the sport. Porsche would continue to dominate in the Group C category, however, while the IMSA Category was able to succeed in its goal of attracting a wide range of cars. Group C cars were limited on the amount of fuel they could use per race, while the IMSA cars had displacement criteria based on their minimum weight.
In the Group C category, competition quickly grew as they had better chances of achieving a podium finish. One such company was 'March', who developed a brand new GTP car for this class. With the experience gained from the BMW M1C Formula 1 project, the company was able to quickly develop the March 82G. The car utilized the aluminum honeycomb monocoque chassis used in the BMW M1C and was configured by Adrian Newey and Robin Herd to accept a wide variety of engines. The suspension was comprised of double wishbones in both the front and the back. The body design was courtesy of Max Sardou. It incorporated many ground effect principles with a distinct open hole in the front between the fenders that helped transfer air to the under-body venturis. The design would continue to change over the years, though it would keep its nickname 'lobster-claw.'
Mounted mid-ship was a Chevrolet V8 engine mounted at 90 degrees. Aluminum was used in the construction to help reduce the overall weight. Fitted with two overhead valves per cylinder, the 350 cubic-inch engine was capable of producing over 600 horsepower. Disc brakes could be found at all four corners, and power was sent to the rear wheels via a five-speed gearbox.
The March 82G made its racing debut at the Daytona 24 Hours where it qualified on pole, an exceptional performance on the inaugural IMSA GTP race. Early on in the race, the car was forced to retire due to problems with the gearbox. The second race of the season was at the Sebring 12 Hours. The March 82G would finish in second behind a Porsche 935.
Three additional cars were built with all but one being fitted with a Chevrolet powerplant. The other car had a BMW six-cylinder engine. None of these cars would have much success in the IMSA GTP category. One March 82G was entered by the factory at the Silverstone and Le Man's race in the Group C category, but it did not have much success.
The highlights for the 82G were at the beginning of the season. With the lessons learned, the March factory built the 83G for the following year. Its design was similar to its predecessor. In total, four examples were built to GTP specification and one to Group C. Nissan purchased one of the cars, and Al Holbert purchased the remaining three. Holbert fitted two of them with a Chevy V8 and gave the other a turbocharged flat-six Porsche engine. The Porsche-powered car would prove to be very successful and won every race it was entered in that season. Holbert would win the IMSA Championship that year.
In 1984, March introduced its 84G model. Seven examples were created given a variety of engines including a Buick V6 Turbo, Mazda rotary, Porsche flat-six, and a Chevrolet V8. The changes to the car were minor, but sufficient to give drivers Randy Lanier and Bill Whittington dominant seasons and earning the IMSA championship. This incredible success the March Company was experiencing was to be short-lived, as Porsche introduced their flat-six powered Porsche 962 part way through the season. In the capable hands of Al Holbert and Derek Bell, the Porsche 956 earned five victories during the season.
In 1985, March introduced its 85G model. Eleven examples were built. Two of March's customers were BMW and Nissan, with one of the Nissan-powered cars achieving a World Championship victory at Fuji. Though it was a win, most of the European manufacturers had withdrawn from the race due to the rainy weather and not having proper tires.
The 86G followed the next year and was commissioned by Nissan in the Group C category, and by BMW for use in GTP racing. Another example was created for a privateer and would become the final GTP/C car built by the March factory.
There were ten examples of the March 86G constructed. BMW purchased six examples and two were later destroyed in fires caused by the turbochargers. Nissan purchased four examples and prepared them for Le Mans. The BMW cars were run in the IMSA GTP series.
These new March cars were designed by Gordon Coppuck and originally carried the name '86S', with the 'S' symbolizing sport. The cars were very lightweight, thanks in part to their aluminum honeycomb chassis with magnesium bulkheads. The BMW cars were fitted with 2-liter engines that were given additional performance with the assistance of turbochargers.
BMW raced the cars during the season with some success. Most of their attempts at overall victory eluded them due to mechanical or other problems. When BMW halted its support, two of the cars were purchased by Gianpiero Moretti. These two cars were given Buick engines. One was a turbocharged V-6, and the other was a normally-aspirated V-8 unit. Both of these cars raced until 1988.
The BMW 86G cars were very fast, competitive, and lightweight. Their shortcomings were their lack of reliability. With further development, testing, and fine-tuning, they could have become consistent front-runners.
by Dan Vaughan