The series launched in 2006 as Prototype Lites, using single-seat open-cockpit prototype cars powered by four-cylinder and motorcycle-derived engines in tiered L1, L2, and L3 classes. The format was oriented toward affordability and driver development — entry-level prototype experience on major circuits without the cost of a full LMP2 or higher-tier programme.
The transformative upgrade came in 2017 when the series adopted the LMP3 specification: the [[lmp3|LMP3]] closed-cockpit prototype sportscar standard developed by the ACO for global use. Cars meeting this spec included the Ligier JS P3 and the Duqueine M30-D08, powered by a naturally aspirated Nissan V8 5.6-litre engine producing approximately 420 horsepower in a minimum-weight package of 930 kilograms. The move to LMP3 directly aligned the Prototype Challenge with the international LMP3 class, meaning graduates could transition into European or global LMP3 programmes or step up to [[imsa-dpi-class|DPi]] and [[imsa-gtp|GTP]] programmes with directly relevant experience.
Most Prototype Challenge rounds ran as support events to the WeatherTech Championship at the same circuits and same weekends, giving drivers exposure to major-league conditions — broadcast infrastructure, pit lane protocol, professional crew interaction — without the cost of a full championship programme. Standard race duration was 1 hour 45 minutes, with the Daytona season opener extended to 3 hours in recognition of the circuit's prestige.
The series produced a consistent stream of drivers who progressed into higher IMSA classes and international prototype racing. The 2022 champion was Tõnis Kasemets of Estonia, with Wulver Racing taking the teams' title in the series' final season. Earlier in the LMP3 era, champions included Dakota Dickerson and Josh Sarchet (2021) and Matthew Bell with Naveen Rao (2020).
The IMSA Prototype Challenge ended after the 2022 season and was replaced in 2023 by the IMSA VP Racing SportsCar Challenge, reflecting IMSA's broader restructuring of its support and entry-level categories.
The [[lmp3|LMP3]] class that defined the Prototype Challenge's final five seasons is well-represented in simulation. iRacing's LMP3 car (the Ligier JS P320 variant) mirrors the regulatory specification closely, giving sim racers access to the same class of machinery that competed in the real series. The Prototype Challenge's track list — Daytona, Sebring, Watkins Glen, Road Atlanta, Laguna Seca — maps directly onto circuits available in major sim platforms.
[[imsa-weathertech-sportscar-championship|IMSA WeatherTech SportsCar Championship]] — parent series
[[lmp3|LMP3 class]] — the car specification used 2017–2022
[[imsa|IMSA]] — sanctioning body
[[daytona-international-speedway|Daytona International Speedway]] — extended-format season opener
[[endurance-racing|Endurance racing]] — the broader discipline
[[iracing|iRacing]] — sim platform with LMP3-spec cars
[[imsa-dpi-class|DPi / GTP]] — the class graduates stepped into
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