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Willow Springs - January 17 (OnGrid / Super GT Cup)

Event Type
Track Event
Event Organizer
Standard HPDE rules apply for the day ... unless you're competing in Super GT Cup.

Rules (As of 12/23 --

SUPER GT CUP is a Time Attack competition for American cars.
Cars allowed:
Camaro, Corvette, Viper, Mustang (including Shelby and GT4),
  • Any Other American cars are subject to approval by SUPER GT CUP Stewards
  • Electric or Hybrid vehicles are not allowed
  1. SUPER GT CUP has a class calculator based on points.
  2. Points are divided in 2 parts: ‘CAR BASE’ points, ‘MODIFICATION POINTS’
    • CAR BASE points: every type of car will have a unique ‘Base’ points count
    • MODIFICATION POINTS: Points base on specific mods in the car
      • All mods including factory options must be selected. (ex: Camaro ZL1 1LE must select “Level 2 Wing” under aero) (Updated 11/3/20)
  3. The sum of BASE and MODIFICATION points will define the class for the car. There are 4 different classes:
    1. STREET (total points : <=5)
    2. MOD (total points : 5.125 – 11)
    3. SUPERMOD (total points : 11.125 – 16)
    4. RACE (total points : >16)
  4. Max front tire width for STREET class is 305mm. (Updated 11/11/20)
  5. Level 3 R-compound tires are allowed only in SUPERMOD and RACE. (Updated 11/11/20)
  6. Cars in STREET class may remove their rear seats only if rollbar is installed. (Updated 11/11/20)
The class calculator will determine what Class the car will belong in (Updated 11/12/20)
Download Class Calculator
Submitted Class Calculators
Please submit your completed Class Calculator to [email protected] with your First and Last name as the file name.
*You must submit your completed Class Calculator before the event in order to compete*

  1. Any modification to a competitor’s vehicle must be allowed within said class and the rule book along with the CCR. If you have any questions, please email [email protected].
  2. Only 1 driver per entry allowed. No teams allowed or multiple drivers sharing the same car. (Updated 11/3/20)
  3. The same vehicle may not be used for multiple entries. (i.e. you cannot swap tires to bump down a class and compete with the same car in 2 classes.) (Updated 11/3/20)
  4. Drivers my switch vehicles between rounds, but must be re-classed based on new vehicle. (Updated 11/3/20)
  5. Times from vehicles not registered for SUPER GT CUP will not be counted.
  6. SUPER GT CUP Stewards may re-class any vehicle if the vehicle greatly exceeds its classes performance capability.
  1. Competing vehicles must be from a recognized manufacturer and have been mass produced for the general public with a VIN#.
  2. Full tube chassis are not allowed unless part of the OEM chassis have been cleared by an SUPER GT CUP Race Steward prior to the event.
  3. Vehicles must resemble their stock body by keeping true to the original outline and overall body shape.
  1. One internal combustion engine is allowed per vehicle.
  2. Unleaded gas and E85 are the only fuels permitted.
  3. Engine swaps are permitted as long as the new engine has the same amount of cylinders as the factory engine.
  1. OEM seatbelt allowed
  2. 4 point harness must be Anti-SubMarining (ASM). ex: Schroth Quickfit
    • 4 point ASM harness must be designed for your car ie: don’t use a 4 point ASM designed for a Mustang in a Camaro
  3. Vehicles equipped with 5 or 6 point harnesses must have a 4 point roll bar at minimum.
  4. Brake lights must be fully operational in all classes.
  5. Lexan/Acrylic Windows are allowed only in RACE class
  6. Removal of trunk interior allowed in Street
  7. Interior removal BEHIND B PILLARS as long as it does not compromise safety is allowed in "MOD"
  8. Interior removal BEHIND A PILLARS as long as it does not compromise safety "SUPERMOD"
  9. Unlimited interior removal ( i.e. Gutted Doors, Dashboard removal, Heater Core removed ) is ONLY ALLOWED in Race class.
  10. Passenger seat removal allowed in MOD class and above
  11. Head and neck restraints are mandatory for RACE class, and highly recommended for every other class.
  12. All competing vehicles must pass onsite inspection by an SUPER GT CUP Race Steward or have been inspected by an SUPER GT CUP approved shop prior to the event.
  13. SUPER GT CUP Race Stewards may inspect competitors’ vehicles at any time to ensure vehicle complies to the rules and safety standards.
  14. All vehicles must have a front and rear tow hooks or straps.
  15. Competitors must run any and all decals required by SUPER GT CUP organizers.

Round 1 --- Fight!