The Thunderdome rules
VTA (Oval & On-Road)
v2Class RulesVTAEffective Sep 4, 2025· Updated 3 months ago
Summary of recent changes
Official ThunderDome rulebook (rev 2025-09-04). Discipline: Oval & On-Road.
Spec sheet
Governing
- Notes
- 5mm min ride height; SXT Black only
Motor & ESC
- Motor type
- Spec brushless
- Motor turn
- 25.5T
- Spec motor
- Gravity GRC2025 Scale Spec 25.5
- ESC
- Blinky / zero-timing (2S ROAR approved)
- Blinky mode
- zero_blinky
- Max motor timing
- 30° (fixed)
Battery & power
- Battery chemistry
- LiPo
- Cells
- 2S
- Max voltage
- 8.40V
- Hard case
- Required
Tires
- Spec tire
- Protoform VTA / Gravity G-Spec VTA / HPI Vintage Racing
- Tire additive
- Spec sauce only
Weight & body
- Min weight
- 1400 g
- Body
- Any VTA approved body
Chassis & Suspension
- Chassis
- 4WD 1/10 touring car, mid or rear motor
1.Chassis Spec
Four Wheel Drive 1/10th scale touring car. Mid motor or rear motor.
2.Weight Spec
Minimum 1400g in race-ready trim.
3.ESC
Any 2s 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
Protoform VTA tires (rear 31mm #10139-00 / front 26mm #10140-00) / Gravity G-Spec VTA tires #GRC146 / HPI Vintage Racing tires. Sidewall glueing allowed.
6.Motor Spec
Gravity GRC2025 Scale Spec 25.5, 30 degree fixed timing.
7.Body Spec
Any VTA approved body.
8.Ride Height Spec
5mm minimum.
9.Race Spec
30 lap qualifiers – 50 lap mains (OVAL) / 5 minute qualifiers – 5 minute mains (ON-ROAD).
10.Tire Sauce
SXT Black ONLY.
Version history
v1Published.
Jul 28, 2026v1Pre-official seed content (archived before load)
Aug 3, 2026