Sat, Apr 25 - Sun, Apr 26, 2026

Speed SF 2.5hrs Endurance Race Registration

Buttonwillow Raceway - Classic

About this event

    

 

2.5 hours Endurance Race - Round 1 

4/25 - 4/26 (Sat - Sun)  Buttonwillow Circuit

Saturday:

  • Practice and Qualifying

Sunday:

  • 2.5 hours Race

Early Sign up price: $350  (Regular price $550)

  • The race format, regulations, and pricing remain identical to those of our previous event. You can find more details on our blog at the following link: Rules / Blog
  • Feel free to let us know if you have any questions by emailing us at info@speedsf.com

Rules:

  • Tires: Any tires
  • No minimum driver requirement 
  • Vehicles must comply with SCCA, NASA, Lucky Dog, PCA, WRL, wheel-to-wheel racing rules

Classification:

  • Three classes: Group A / B /C
  • Classes will be determined by Saturday's qualifying time. We will classify your car based on our experience and the vehicle's performance at the current race. 
  • Group A - Target lap time: 1:53 - 1:58* (Buttonwillow Circuit)

    • Example: M3, Corvette, Cayman, etc

  • Group B - Target lap time: 1'59 - 2'04*

    • Example: 350z, S2000, Spec E46, Mustang, Boxster, etc

  • Group C - Target lap time: 2'05+*

    • Example: Miata, E30, IS300, 944, E36 325i/328i, etc

  • *Actual Classing will be determined by historical data and the build reports supplied by teams after the qualifying session

Pit stops:

  • 1 Minimum pit stop required. 
  • Pit stops will only be performed at the hot pit with a 5-minute required pit time. (In and out of the paddock/hot pit)
  • Refuel must be performed in the hot pit.
  • Tire change is allowed after refueling.
  • A timer will be placed on every vehicle during the pit stop.

 

Race pace:

  • We will set a delta lap time after the qualifying session. The delta is -1 sec. If your vehicle goes faster than our pre-set lap time by 1 sec of your class, a penalty (Black flag) will be issued.
  • The first black flag will be a drive-through warning letting you know you have exceeded the time. The second black flag will be a two- (2) minute hold. The third black flag will be a five- (5) minute hold. The fourth black flag will result in a disqualification for that race, and the vehicle will be removed from competition for the rest of the day. 

 


 

Event requirements

Requirements:

  • No minimum driver requirement for this race.
  • 18+ years old with a valid US or International driver's license
  • Minor (16+) requires approval.
  • NASA SCCA race licenses are required. Lucky Dog or other racing series are allowed with demonstrated/documented racing experience.
  • My laps / AMB transponder is required. Rental is available.
  • Vehicles must comply with SCCA, NASA, Lucky Dog, PCA, WRL, wheel-to-wheel racing rules

 

Entries (12)

JM
Jean-Luc Martin
NF
Nick Fogler
FY
Fan You
AA
Anthony Altwer
JB
Jeevan Bawa
RC
Rick Cameron
CS
Christian Strain
VB
Vitali Barkouski

Buttonwillow Raceway - Classic

Buttonwillow, CA
Download track map
Download track map

Organizer

Endurance Racing organized by

Speedsf.com

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Speed SF 2.5hrs Endurance Race Registration

Sat, Apr 25 - Sun, Apr 26, 2026