Source: National Auto Sport Association (2026)
Key Findings at a Glance
- → 10 spec series NASA offers 10 spec racing classes, including Spec E30, Spec E46, Spec Miata, and the flagship NASA Prototype class, alongside less restrictive classes like Super Touring and German Touring Series. [National Auto Sport Association]
- → 84 cars entered ChampCar’s Eye of the Storm Sebring Enduro (Sept 19-20, 2026) at Sebring International Raceway had 84 cars entered, the largest field among ChampCar’s next three scheduled races. [ChampCar Endurance Series]
- → 10 race weekends The Hoosier Racing Tire SCCA Super Tour consists of 10 race weekends held at 10 premier tracks across the United States, running from January through July as part of the U.S. Majors Tour. [Sports Car Club of America (SCCA)]
- → Under 20 pages World Racing League keeps its full rulebook to less than 20 pages while balancing a wide range of vehicles by power-to-weight ratio for close, multi-class endurance competition. [World Racing League]
- → More than 100 clubs The United Kingdom has more than 100 motorsport clubs that organize their own championships, according to Wikipedia’s compiled list of motorsport championships. [Wikipedia – List of motorsport championships]
- → $500 cars 24 Hours of Lemons bills itself as an endurance racing series on dedicated road courses built around cars valued at $500, and currently lists 10 events available through Seat4Sale. [Seat4Sale]
- → 6 events for 2026 American Endurance Racing’s 2026 season schedule includes six events at Watkins Glen, VIR, Summit Point, Road America, Mid Ohio, and NJMP. [American Endurance Racing]
The National Auto Sport Association runs 18 separate road racing series nationwide, including 10 dedicated spec classes, all under one unified rulebook, according to NASA’s 2026 program data. That scale sits alongside other major amateur options such as the SCCA’s Hoosier Racing Tire Super Tour, ChampCar Endurance Series, World Racing League, American Endurance Racing, and 24 Hours of Lemons — each with its own entry counts, schedules, and rulebooks. This breakdown compares car counts, race weekends, and rules across the biggest names in grassroots road racing for 2026.
1How Many Series Does NASA Run Nationwide?
The National Auto Sport Association operates 18 road racing series nationwide, including 10 spec classes such as Spec E30, Spec E46, Spec Miata, and NASA Prototype. A single rulebook governs every region. The SCCA’s Hoosier Racing Tire Super Tour runs a separate 10-weekend schedule at 10 tracks from January through July.
| METRIC | VALUE | SOURCE |
|---|---|---|
| NASA total road racing series | 18 series | National Auto Sport Association |
| NASA spec class series | 10 series | National Auto Sport Association |
| SCCA Hoosier Super Tour race weekends | 10 weekends | Sports Car Club of America (SCCA) |
| Source: National Auto Sport Association | ||
Ten of NASA’s 18 series fall under strict spec rules, meaning cars like Spec Miata or Spec E46 run near-identical setups that keep costs predictable — a factor drivers researching true costs of amateur racing cars often consider before picking a class. Less restrictive options such as Super Touring and German Touring Series give owners more freedom over setup, still racing under the same NASA rulebook. The SCCA’s Hoosier Racing Tire Super Tour takes a different approach, concentrating its season into 10 weekends at 10 marquee tracks between January and July, feeding results into the U.S. Majors Tour path drivers can track through building a network in amateur racing.
2What Do Endurance Racing Rulebooks Actually Require?
World Racing League keeps its full rulebook under 20 pages, balancing vehicles by power-to-weight ratio instead of make-and-model rules. Race weekends include 20+ hours of track time, races run 8 to 14 hours, and tires need a 180+ treadwear rating. American Endurance Racing’s 2026 season spans six events at Watkins Glen, VIR, Summit Point, Road America, Mid Ohio, and NJMP.
| METRIC | VALUE | SOURCE |
|---|---|---|
| WRL rulebook length | Under 20 pages | World Racing League |
| WRL included track time per weekend | 20+ hours | World Racing League |
| WRL minimum tire treadwear | 180+ treadwear rating | World Racing League |
| WRL race duration | 8-14 hours | World Racing League |
| American Endurance Racing 2026 season events | 6 events | American Endurance Racing |
| Source: World Racing League | ||
A rulebook short enough to read in one sitting lets World Racing League focus on power-to-weight balancing rather than policing individual makes, which explains why grids mix everything from base-model sedans to modified sports cars in the same race. Treadwear ratings of 180 or higher keep tire costs down across those 8-to-14-hour races, a detail budget-minded teams researching different types of motorsport competition tend to notice quickly. American Endurance Racing takes a leaner scheduling approach for 2026, running just six events rather than a full national circuit, with Mid Ohio among the tracks hosting a weekend — the same circuit covered in Mid Ohio’s IndyCar race weekend at the professional level.
3How Many Cars Enter ChampCar’s Biggest Races?
ChampCar’s Eye of the Storm Sebring Enduro at Sebring International Raceway drew 84 entries, its largest field among the next three scheduled races. The Fast Parts Grand Prix at Mid-Ohio logged 64 cars, and The Thompson 12 at Thompson Speedway attracted 38 entries for its August 2026 date.
| METRIC | VALUE | SOURCE |
|---|---|---|
| ChampCar – The Thompson 12 entries | 38 cars | ChampCar Endurance Series |
| ChampCar – Fast Parts Grand Prix at Mid-Ohio entries | 64 cars | ChampCar Endurance Series |
| ChampCar – Eye of the Storm Sebring Enduro entries | 84 cars | ChampCar Endurance Series |
| Source: ChampCar Endurance Series | ||
The gap between Thompson Speedway’s 38 entries and Sebring International Raceway’s 84 shows how track reputation and calendar timing shape car counts, with Mid-Ohio’s 64-car Fast Parts Grand Prix field landing between the two. Teams scouting for their next weekend often start with regional listings like local amateur racing events for the season before committing to a bigger national date. Entry fees and prep costs for a field of 84 cars differ sharply from a 38-car grid, a gap covered in more detail in what these amateur racing cars actually cost teams to run.
4Which Grassroots Series Have the Most Events Listed?
Chin Track Days leads Seat4Sale’s listings with 24 available events, ahead of 24 Hours of Lemons at 10, Apex Driving Academy at 4, and both American Endurance Racing and Formula Race Promotions at 2 each. Lemons builds its series around cars valued at $500 on dedicated road courses.
| METRIC | VALUE | SOURCE |
|---|---|---|
| 24 Hours of Lemons events available | 10 events | Seat4Sale |
| Chin Track Days events available | 24 events | Seat4Sale |
| American Endurance Racing events available (Seat4Sale listing) | 2 events | Seat4Sale |
| Apex Driving Academy events available | 4 events | Seat4Sale |
| Formula Race Promotions events available | 2 events | Seat4Sale |
| Source: Seat4Sale | ||
Chin Track Days outpaces every other series in Seat4Sale’s directory with 24 listed events, reflecting a track-day format built for open lapping rather than wheel-to-wheel points racing. 24 Hours of Lemons sits well behind at 10 events but stands apart on cost, building its entire series around cars valued at $500 — a budget threshold covered in the real costs behind cheap amateur racing cars. Apex Driving Academy and Formula Race Promotions round out the directory with 4 and 2 listed dates respectively, giving drivers a much smaller pool of scheduled weekends to choose from. Drivers comparing format against cost can check these options against broader listings in different categories of motorsport events before booking a season.
5How Far Back Does Grassroots and Championship Racing Go?
The UK counts more than 100 motorsport clubs running their own championships, per a Wikipedia-compiled list. Professional racing dates back further: the IndyCar Series traces to 1905, Formula One’s World Championship began in 1950, and Formula E launched its 2014/15 season. USA Today ranked the MOTUL Petit Le Mans No. 10 on its 2026 10Best Motorsports Race list.
| METRIC | VALUE | SOURCE |
|---|---|---|
| UK motorsport clubs organizing championships | 100+ clubs | Wikipedia – List of motorsport championships |
| IndyCar Series founding | 1905 year | Wikipedia – List of motorsport championships |
| Formula One World Championship start | 1950 year | Wikipedia – List of motorsport championships |
| Formula E World Championship start | 2014/15 season | Wikipedia – List of motorsport championships |
| USA Today 10Best Motorsports Race ranking, No. 10 entry | MOTUL Petit Le Mans named event | USA TODAY 10Best |
| Source: Wikipedia – List of motorsport championships | ||
That figure of 100-plus UK clubs, even sourced from a 2007 compilation, points to a grassroots culture that predates most professional series covered in a look at historic motorsport categories by decades. Formula One’s championship structure, running since 1950, gets tracked in detail across total wins by every F1 driver; the IndyCar Series’ 1905 roots make it older than nearly every series in this comparison. Formula E’s arrival in the 2014/15 season, covered further in how electric racing categories are organized, shows how recently electric racing joined a calendar that already included century-old events, and the MOTUL Petit Le Mans’ No. 10 ranking on USA Today’s list confirms endurance racing still draws mainstream recognition alongside these grassroots numbers.
Complete Data Reference
Sortable table of all verified data points. Click any column header to sort.
| Metric | Value | Source | Year |
|---|---|---|---|
| NASA total road racing series | 18 series | National Auto Sport Association | 2026 |
| NASA spec class series | 10 series | National Auto Sport Association | 2026 |
| SCCA Hoosier Super Tour race weekends | 10 weekends | Sports Car Club of America (SCCA) | 2026 |
| WRL rulebook length | Under 20 pages | World Racing League | 2026 |
| WRL included track time per weekend | 20+ hours | World Racing League | 2026 |
| WRL minimum tire treadwear | 180+ treadwear rating | World Racing League | 2026 |
| WRL race duration | 8-14 hours | World Racing League | 2026 |
| ChampCar – The Thompson 12 entries | 38 cars | ChampCar Endurance Series | 2026 |
| ChampCar – Fast Parts Grand Prix at Mid-Ohio entries | 64 cars | ChampCar Endurance Series | 2026 |
| ChampCar – Eye of the Storm Sebring Enduro entries | 84 cars | ChampCar Endurance Series | 2026 |
| American Endurance Racing 2026 season events | 6 events | American Endurance Racing | 2026 |
| 24 Hours of Lemons events available | 10 events | Seat4Sale | 2026 |
| Chin Track Days events available | 24 events | Seat4Sale | 2026 |
| American Endurance Racing events available (Seat4Sale listing) | 2 events | Seat4Sale | 2026 |
| Apex Driving Academy events available | 4 events | Seat4Sale | 2026 |
| Formula Race Promotions events available | 2 events | Seat4Sale | 2026 |
| UK motorsport clubs organizing championships | 100+ clubs | Wikipedia – List of motorsport championships | 2007 |
| IndyCar Series founding | 1905 year | Wikipedia – List of motorsport championships | 2007 |
| Formula One World Championship start | 1950 year | Wikipedia – List of motorsport championships | 2007 |
| Formula E World Championship start | 2014/15 season | Wikipedia – List of motorsport championships | 2007 |
| USA Today 10Best Motorsports Race ranking, No. 10 entry | MOTUL Petit Le Mans named event | USA TODAY 10Best | 2026 |
Methodology
Entry counts for ChampCar events reflect registration numbers as of the research date and are likely to change before race day. The UK club count comes from a Wikipedia-compiled list last dated 2007, so it may undercount current club activity. Some series (e.g., NASA, SCCA) publish regional variations that are not fully broken out here.
- Sources consulted: 10
- Sources cited: 7
- Data range: 2007-2026
- Freshness: 18 current-year, 0 last-year, 1 older
- Update schedule: Quarterly
Frequently Asked Questions
How many racing series does NASA operate nationwide?
The National Auto Sport Association runs 18 separate road racing series across its regional chapters, all governed by one unified rulebook. This includes 10 dedicated spec classes such as Spec Miata and Spec E46, plus less restrictive options like Super Touring. The shared structure lets drivers move between regions while racing under familiar rules. [National Auto Sport Association]
What are NASA’s spec racing classes?
NASA fields 10 spec racing classes, including Spec E30, Spec E46, Spec Miata, and its flagship NASA Prototype class. These classes require near-identical cars with tightly controlled modifications, keeping costs down and competition close. Alongside them, NASA also runs less restrictive categories like Super Touring and German Touring Series for drivers who want more setup freedom. [National Auto Sport Association]
How is the SCCA’s Hoosier Racing Tire Super Tour structured?
The Hoosier Racing Tire SCCA Super Tour spans 10 race weekends at 10 premier tracks across the country, running January through July as part of the U.S. Majors Tour. Results from these weekends feed into the SCCA National Championship Runoffs, giving amateur racers a clear path from regional competition toward a national title. [Sports Car Club of America (SCCA)]
What makes the World Racing League rulebook different from other series?
World Racing League keeps its entire rulebook under 20 pages, balancing a wide mix of vehicles by power-to-weight ratio rather than strict make-and-model rules. Race weekends include more than 20 hours of track time, with races lasting 8 to 14 hours and tires rated 180+ treadwear so cars can finish without extra pit stops for rubber. [World Racing League]
How competitive are ChampCar’s endurance events?
Entry counts vary widely by event. ChampCar’s Eye of the Storm Sebring Enduro at Sebring International Raceway drew 84 cars, its largest field among the next three scheduled races, while the Fast Parts Grand Prix at Mid-Ohio logged 64 entries and The Thompson 12 at Thompson Speedway saw 38 cars sign up for its August 2026 date. [ChampCar Endurance Series]
What is 24 Hours of Lemons known for?
24 Hours of Lemons is an endurance series built around cars valued at $500, run on dedicated road courses rather than ovals or autocross lots. Through Seat4Sale, the series currently lists 10 available events, giving budget-focused teams a lighthearted but genuinely competitive way to race low-cost machinery against similarly priced rivals nationwide. [Seat4Sale]
How many events is American Endurance Racing hosting in 2026?
American Endurance Racing’s 2026 calendar includes six events, held at Watkins Glen, Virginia International Raceway, Summit Point, Road America, Mid-Ohio, and New Jersey Motorsports Park. The compact schedule concentrates competition at well-known road courses, letting teams plan a full season around a manageable number of weekends rather than a sprawling national circuit. [American Endurance Racing]
Just how widespread is grassroots motorsport in the UK?
According to a Wikipedia-compiled list of motorsport championships, the UK is home to more than 100 motorsport clubs that organize their own championships. Though the source data dates to 2007, it points to a long-standing culture of independently run, club-level competition spread across the country well beyond the professional racing scene. [Wikipedia – List of motorsport championships]
Sources & References
- National Auto Sport Association. “NASA Road Racing.” https://drivenasa.com/road-racing/. Accessed 2026-08-10.
- ChampCar Endurance Series. “ChampCar Endurance Series – Race Schedule and Entries.” https://champcar.org/web/. Accessed 2026-08-10.
- Sports Car Club of America (SCCA). “On Track – Hoosier Racing Tire SCCA Super Tour.” https://www.scca.com/pages/on-track. Accessed 2026-08-10.
- World Racing League. “About WRL.” https://www.racewrl.com/about-wrl. Accessed 2026-08-10.
- Wikipedia – List of motorsport championships. “List of motorsport championships.” https://en.wikipedia.org/wiki/List_of_motorsport_championships. Accessed 2026-08-10.
- Seat4Sale. “24 Hours of Lemons – Series Listing.” https://seat4.sale/series. Accessed 2026-08-10.
- American Endurance Racing. “American Endurance Racing – 2026 Season.” https://americanenduranceracing.com/. Accessed 2026-08-10.
Last updated: August 10, 2026
