March Engineering had already established a strong presence in American open-wheel racing through the early 1980s, and the 86C represented the culmination of that development. The car was entrusted to Adrian Newey — who would later become one of Formula 1's most celebrated designers — and reflected sophisticated aerodynamic thinking for the era. The chassis was compatible with multiple engine configurations, primarily running the Ford-Cosworth DFX turbo V8, but teams also fitted the Buick Indy V6 turbo and the Ilmor-Chevrolet 265-A Indy V8 turbo engine, depending on their commercial relationships and performance targets.
The 86C's 1986 campaign was a near-total sweep of the CART IndyCar championship. The car won 14 of the 17 races on the calendar and collected 13 pole positions, leaving rival chassis with almost no room to compete. Bobby Rahal drove the 86C to victory at the 1986 Indianapolis 500, and the title followed in kind, giving March back-to-back periods of dominance in American open-wheel racing following their strong 1985 showing.
The scale of the winning margin placed the 86C alongside the most lopsided seasons in CART history. Rival manufacturers were unable to mount a meaningful challenge, and the season effectively became a contest between March-equipped teams rather than a broader field.
Owing to its exceptional competitiveness, several teams continued to race the 86C into the 1987 and even 1988 seasons rather than switching to newer machinery. The most notable instance came at the 1987 Indianapolis 500, when the Penske team encountered problems with their in-house PC-16 chassis during practice and qualifying. Mid-month, Penske made the decision to revert to the 86C, a proven car they had raced the previous year. The gamble paid off spectacularly: Rick Mears qualified on the front row, and Al Unser Sr. went on to win the race, giving the 86C back-to-back victories at Indianapolis across consecutive years.
Later in the 1987 season, Rick Mears added another win for the chassis at Pocono, bringing the 86C's 1987 total to two victories despite no longer being the current-specification car. This longevity was a testament to the soundness of Newey's original design.
The March 86C occupies an important place in IndyCar history both for the scale of its on-track dominance and for its connection to Adrian Newey's early career. Newey would go on to design championship-winning cars for Williams, McLaren, and Red Bull Racing in Formula 1, but the 86C represented his breakthrough work at the highest level of American open-wheel competition. The chassis later saw additional racing life in the American Indycar Series, extending its operational career well beyond the original two CART seasons for which it had been built.
For March Engineering, the 86C was the high-water mark of their American program, cementing the British constructor's reputation as the dominant chassis supplier to IndyCar teams through the mid-1980s.