GT World Challenge America - Round 13

Round 13 of the GT World Challenge America takes place at Indianapolis Motor Speedway in 2025. This race serves as the season finale and features a unique format that sets it apart from other rounds in the championship. The Indianapolis 8 Hour stands as the longest race on the GT World Challenge America calendar and requires teams to field three drivers instead of the typical two-driver format used throughout the season.

Race Format and Structure

The Indianapolis 8 Hour follows an endurance racing format that spans eight hours of continuous competition. Teams must use three drivers who share the driving duties across the race distance. The event runs exclusively for GT3-class race cars and includes mandatory pit stops for fuel, tires, and driver changes. The SRO Motorsports Group manages the series, while the United States Auto Club provides sanctioning.

The 2025 season marks a notable year for tire regulations. Series organizers have banned tire warmers to reduce operating costs for competing teams. This rule change affects how teams approach their pit stop strategies and driver stints throughout the race.

Indianapolis Motor Speedway Road Course

Indianapolis Motor Speedway uses its infield road course configuration for the GT World Challenge America event. The circuit measures 2.605 miles in length and features 14 turns that combine portions of the famous oval with the internal road course sections. Drivers navigate both the flat infield sections and portions of the banked oval, which has corners angled at 9 degrees and 11 minutes.

The facility earned its nickname "The Brickyard" from its original construction. Workers laid 3.2 million bricks to pave the track surface when it opened in 1909. Today, one yard of original bricks remains exposed at the start-finish line as a tribute to this heritage. Race winners often participate in the tradition of kissing the bricks after their victories.

Venue Capacity and Scale

Indianapolis Motor Speedway holds the distinction as the highest-capacity sports venue in the world. The permanent grandstands seat 257,325 spectators, with total capacity reaching approximately 400,000 when infield areas are included. The speedway covers such a large area that it could contain several famous venues within its perimeter, including the Rose Bowl, Yankee Stadium, and Vatican City.

Competing Manufacturers and Teams

The 2025 GT World Challenge America season includes entries from 10 manufacturers. Audi, Aston Martin, BMW, Corvette, Ford, Lamborghini, McLaren, Mercedes-AMG, Nissan, and Porsche provide GT3 machinery for the championship. Each manufacturer develops race cars based on production models that meet strict GT3 technical regulations.

Teams competing in the series include established operations such as Random Vandals Racing, Turner Motorsport, DXDT Racing, and Heart of Racing Team. The Indianapolis 8 Hour format attracts additional entries beyond the regular season competitors, as teams add a third driver to meet the endurance race requirements.

GT3 Technical Specifications

GT3 cars form the sole class for GT World Challenge America competition. These race cars feature production-based chassis with extensive modifications for racing. All competitors must use Pirelli tires as specified by series regulations. Teams must replace original equipment manufacturer flexible brake lines with stainless steel brake lines for safety reasons.

GT3 regulations balance performance across different manufacturers through a combination of weight adjustments, aerodynamic restrictions, and engine management systems. This technical framework allows various car models to compete on equal terms despite different engine configurations and chassis designs.

Series History and Background

GT World Challenge America traces its roots to the Pirelli World Challenge, which began in 1990. The SRO Motorsports Group acquired the series in 2018 and rebranded it as Blancpain GT Series America. The championship adopted its current GT World Challenge America name in 2020, aligning with SRO's global GT World Challenge brand.

The Indianapolis 8 Hour debuted in 2020 as the first endurance sports car race held at Indianapolis Motor Speedway. This event filled a gap in American endurance racing and provided a significant challenge for GT World Challenge America teams. The race quickly established itself as a premier event on the championship calendar.

Indianapolis Motor Speedway Legacy

Construction crews completed Indianapolis Motor Speedway in 1909, with the first race taking place on August 14 of that year. The facility became the original "speedway," as it was the first racing venue to use that term. The speedway hosted 66 automobile races during three holiday weekends in 1910 before transitioning to its focus on the Indianapolis 500.

The venue has hosted various racing series beyond its famous May classic. Formula One competed at Indianapolis from 2000 to 2007 for the United States Grand Prix. The speedway stands as one of only three tracks worldwide to host races from the Triple Crown of motorsports, joining Monaco and Le Mans in this distinction.

Support Series and Race Weekend Activities

The GT World Challenge America race weekend at Indianapolis Motor Speedway includes several support series. Pirelli GT4 America features GT4-class cars in sprint races. GT America provides a platform for amateur drivers in GT3 and GT4 machinery. The Toyota GR Cup North America showcases spec racing in identical GR86 models.

TC America brings touring car competition to the weekend schedule, while McLaren Trophy America features one-make racing in McLaren sports cars. These support series provide continuous on-track action throughout the race weekend and showcase different forms of sports car competition.

What Makes This Event Stand Out

The Indianapolis 8 Hour differs significantly from other GT World Challenge America rounds. While most races in the series run for 90 minutes with two drivers, this endurance race requires eight hours of competition and three drivers per car. Teams must manage fuel consumption, tire wear, and driver fatigue across a much longer distance.

The Indianapolis Motor Speedway Museum sits on the speedway grounds and houses a collection of historic race cars. Visitors can view Indianapolis 500-winning machines and learn about the venue's role in American motorsports history. The museum provides context for the speedway's significance beyond the current GT World Challenge America event.

Round 13 at Indianapolis Motor Speedway represents the culmination of the GT World Challenge America season. Championship positions are decided through this endurance race, where reliability and consistency matter as much as outright speed. The combination of historic venue, demanding format, and championship implications creates a compelling conclusion to the racing season.