As we build up to this year’s Rolex 24 at Daytona, RACER.com is pleased to bring you a series of excerpts from IMSA 1969-1989 by Mitch Bishop and Mark Raffauf. The soon-to-be-released inside history of IMSA’s first two decades is currently available for pre-order from Octane Press, and as a RACER.com reader, you can get $10 off by applying the discount code RACER19 at checkout. Click here for ordering information, and look for the final except on Thursday.

BMW of North America’s racing group was established in 1975 in an effort to support the company’s growth in the lucrative US performance car market. Unfortunately, the company did not have an IMSA championship to show for the investments in the BMW 3.0 CSL and the turbocharged BMW 320i. With just one or two cars pitted against a host of Porsches, the odds were not in their favor. The tube frame M-1 Procar crushed the GTO competition in 1981 but was underpowered in IMSA’s top class.

Something had to be done to narrow the gap. Former SCCA executive Jim Patterson, who took over the BMW North America racing program in 1978, saw the newly minted GTP rules as a way to get back in the game. Working with partner March Engineering, a unique new prototype was unveiled in early 1981 that would become the basis for a long, successful supply of GTP cars to the IMSA field from the British company.

Designed by French aerodynamics expert Max Sardou and BMW engineer Raine Bratenstein, the car was dubbed the BMW M-1/C. It was built around a March Engineering aluminum monocoque and featured two distinctive pontoons at the front that were designed to channel airflow to both the radiators and twin ground-effects tunnels for maximum downforce.

The car was initially fitted with a 3.5-liter, six-cylinder, normally aspirated BMW engine, and entered for the first time at the Riverside 6 Hours in April 1981 with David Hobbs and European endurance veteran Marc Surer at the wheel. Featuring sponsorship livery from Kenwood audio, the pair finished a credible sixth place, albeit eleven laps down to the winning 935 piloted by Fitzpatrick and Busby.

A week later at Laguna Seca, Hobbs placed sixth again, this time one lap down to the new Lola T-600 with Brian Redman at the wheel. Although down on power, Hobbs managed to put the car on the front row at both Lime Rock and Mid-Ohio. The dawn of the GTP era had arrived.

The first few races proved the M-1/C had real potential and the decision was made to further develop the chassis and engine. The long-term plan was to install the 1.5-liter turbocharged BMW motor being developed for Formula One, but that engine wasn’t ready and would never be used in the March. Instead, the team force-fit the same turbocharged 2.0-liter, four-cylinder engine that had been used successfully in the McLaren-engineered BMW 320i program. Since the M-1/C had not been designed for that power plant, it required a cooling work-around for a motor that produced 600 to 675bhp with the boost turned up.

Results were mixed after the change. The new engine debuted at Sears Point in August. The car was fast and competitive, but ultimately unreliable. A fourth place at Portland would turn out to be the team’s best finish. Despite stating long-term commitments early on, BMW once again left IMSA racing at the end of the year, this time to focus on its Formula One program. Even with this setback, March Engineering continued to develop the chassis for 1982 when an upgraded version dubbed the March 82G was offered to customer teams. That decision turned out to be a good one for both March and IMSA, as it provided a well-developed customer chassis for different engine options.

The biggest story of the 1981 season centered on Lola. After IMSA GTP rules were published in early 1980, Brian Redman approached Lola Cars founder Eric Broadley with the idea of building a car for the new class. In addition to being one of the top drivers of the time in any equipment, Redman was also selling Lola cars for Carl Haas in the United States and was intrigued by the new rules; he saw an opportunity for a customer car and a chance to come out of retirement.

Broadley agreed and the team at Lola came up with the Lola T-600: a simple but powerful wedge-shaped design based on an entirely new chassis that incorporated an aluminum honeycomb monocoque, ground effects tunnels, and side- mounted radiators fed by large, distinctive NACA ducts. To further take advantage of aerodynamics, the rear wheels were covered with access doors that hinged out of the way when needed. A normally aspirated 6.0-liter Chevy V8 prepared by Chaparral produced 630bhp; it was a reliable, proven motor, and parts were readily available. The spirit of the GTP rules came to full fruition for the first time with the new Lola.

“The Lola T-600 was designed as a two-seater racing car rather than a highly modified production-based car, which is what 935s were,” remembered Redman. “The advantage was better weight distribution, although it had a lot less power than the 935. It was hard in the races because the Porsches could turn up the boost in qualifying. We’d qualify somewhere fourth, fifth, sixth, that sort of area. Once the race got going, they couldn’t maintain the high boost pressure without damaging the engines. And we had better handling.”

Having won the 24 Hours of Daytona at the wheel of a Garretson 935, Redman arranged for the first Lola T-600 to be shipped to Cooke-Woods Racing in California in February 1981, where it was prepared largely by Garretson-based mechanics. Redman continued to share the Garretson 935 at Sebring, skipped Road Atlanta in April, and teamed with Rahal in the 935 to finish third at the Riverside 6 Hours. Once testing had satisfied Redman, the T-600 debuted in May at the Laguna Seca sprint round. The car attracted an enormous amount of attention; it didn’t look like anything else in the paddock.

With the BMW M-1/C and the Lola T-600 qualifying fifth and seventh, respectively, the Laguna Seca grid took on a new look, providing a glimpse into the future. Redman methodically worked his way to the front, albeit with help from a turn nine incident that took out Ludwig’s Mustang and Rolf Stommelen’s 935. In its maiden event, the Lola T-600 grabbed the win, marking the first time that a GTP car won a Camel GT race.

Redman went on a tear, winning the next two events at Lime Rock and Mid-Ohio. In total, Redman would win five races and place second in five other events in the Lola, easily taking him to the 1981 Camel GT title. It was the first for him, the first for Lola Cars, and the first for a GTP machine.

Toward the end of the season, a new star driver and car combination began a remarkable run in the ANDIAL/Howard Meister AIR Porsche 935. Stommelen and Harold Grohs won the 1,000-kilometer event at Mosport and the five-hundred-miler at Road America just one week later. The following week, Stommelen and Derek Bell took the nonchampionship five- hundred-mile Lumbermens race at Mid-Ohio. The three-race total in prize money was over $75,000. No car, team, or driver had achieved anything like this streak in sports car racing. More than thirty-five years later, it remains unchallenged: three race wins by Stommelen of five hundred miles or more in just three weeks.

Lola began taking orders for the T-600 from other teams once it started crushing the competition. Ted Field bought three for his Interscope Racing team. John Paul Sr. and Chris Cord each bought one as well. In total, Lola Cars built twelve of the T-600s, which were campaigned successfully not only in IMSA Camel GT racing for the next two seasons, but in the World Endurance Championship of Makes as well.

With the publication of FIA Group C regulations in 1981, some of the new European prototypes began using IMSA racing that same year as a test bed for the following year. GRID, Rondeau, Sauber, and other European constructors appeared at various races. Their presence diversified the fields and produced incredible competition between the new generation prototypes and the now-very-radical-silhouette GTX cars.

In GTO, the newly eligible BMW Procar M-1 was a game changer. Powered by a CSL straight, six-cylinder engine, though now in a modern midengine coupe, BMW gave customers a reliable and potent car. Dave Cowart’s Red Lobster Restaurant–sponsored M-1 dominated, with wins at eleven of the fifteen events. Nine of the top ten in GTO season driver standings used an M-1 exclusively or in at least part of the season.

The Mazda RX-7 again dominated GTU with Dave Kent’s team of Lee Mueller and Walt Bohren finishing one-two in the series. The pair won eleven of the fifteen races between them. Don Devendorf and Electramotive had moved on from GTU in 1981; the team was busy developing the new GTO 280ZX Turbo car for 1982, but they supplied potent Electramotive GTU 280ZXs to customers.