The Thunderdome rules
17.5 Sprint (Oval)
v1Class Rules17.5 SprintEffective Jul 17, 2026· Updated 3 months ago
Summary of recent changes
Official ThunderDome rulebook (rev 2026-07-17). Discipline: Oval.
Spec sheet
Governing
- Governing body
- ROAR
- Notes
- 4mm min ride height
Motor & ESC
- Motor type
- Spec brushless
- Motor turn
- 17.5T
- Spec motor
- Any ROAR-approved 17.5
- ESC
- Blinky / zero-timing
- Blinky mode
- zero_blinky
Battery & power
- Battery chemistry
- LiPo
- Cells
- 2S
- Max voltage
- 8.40V
- Hard case
- Required
Tires
- Spec tire
- Any foam
- Tire additive
- Spec sauce only
Weight & body
- Min weight
- 1502 g
- Body
- Sprint car body (top wing, front wing, cage, etc.)
Chassis & Suspension
- Chassis
- Any 2WD sprint car chassis
1.Chassis Spec
Any 2wd sprint car chassis.
2.Weight Spec
Minimum 1502g in race-ready trim.
3.ESC
Any ESC that is ROAR approved and running in ROAR approved "Blinky" spec software.
4.Battery Spec
ROAR approved 2 cell Lipo hard cased. MAX temp 90F at tech table. 8.40 MAX VOLTAGE.
5.Tire and Wheel Spec
Any foam tires.
6.Motor Spec
Any ROAR approved 17.5 motor.
7.Body Spec
Sprint car body must resemble a real sprint car with top wing, front wing (with rounded corners on both wings), hood, tail tank, cage, bumpers, nerf bars, headers and side panels.
8.Ride Height Spec
4mm minimum.
9.Race Spec
2-4 minute heats / 60-75 lap mains.
10.Tire Sauce
SXT Black ONLY.