Several years later the event received National status which allowed SCCA members to score points needed to qualify for the National Championship Runoffs at the Mid-Ohio Sports Car Course.

Drivers competed in one of twenty-four classes. These groups fall into one of seven different categories:

There are National Championships for twenty-five different classes. These race groups fall into one of seven different categories:

• Production Category – There are four classes in the production category – E Production (EP), F Production (FP), G Production (GP) and H Production (HP). These production-based vehicles are grouped according to their performance potential. Sports cars such as the MGB, Porsche 914, Alfa Romeo Spider, MG Midget, etc., are most often associated with this category.
• Grand Touring Category – Five classes are identified as Grand Touring – they include Grand Touring 1 (GT1), Grand Touring 2 (GT2), Grand Touring 3 (GT3), Grand Touring 4 (GT4) and Grand Touring 5 (GT5). These vehicles are also grouped according to their performance potential. The quickest class, GT1 features cars such as the Ford Mustang and Chevrolet Corvette, while at the other end of the spectrum, GT5 includes the Mini Cooper and Honda Civic. These vehicles are allowed a larger number of modifications than the production category.
• Showroom Stock – Three Showroom Stock categories, Showroom Stock A (SSA), Showroom Stock B (SSB), and Showroom Stock C (SSC), were created by the SCCA to accommodate performance street cars with a minimum amount of modifications required to race. Changes to these vehicles are for safety purposes.
• Sports Racers – These are purpose-built closed-wheel race cars. There are four classes within this group – C Sports Racer (CSR), D Sports Racer (DSR), Sports 2000 (S2) and Spec Racer Ford (SRF). Sports Racers include a variety of chassis’ which may be constructed by the competitor or a race car manufacturer. Several chassis available to Sports 2000 teams; however, they must use a 2.0-liter Ford engine. Spec Racer Ford is tightly controlled, with all drivers competing with the same chassis/engine combination.
• Formula Category – These are also purpose-built race cars. This category includes five classes – Formula Atlantic (FA), Formula Continental (FC), Formula Ford (FF), Formula (F440) and Formula Vee (FV). There are a variety of rules that govern these open-wheel cars.
• American Sedan - This division is comprised of Chevrolet Camaros, Pontiac Firebirds and Ford Mustangs. They use the production-based chassis with modifications to the suspension and brakes.
• Touring 1 – The newest class is Touring 1, which includes the former Showroom Stock GT vehicles and the quicker Showroom Stock A cars. Showroom Stock A competitors are allowed performance enhancements to ensure parity.