Tech Center · Open-Power Sprint Class

Mod SprintClass Guide

Mod Sprint is the open-power sprint class. Any legal motor and ESC may be used on a commercially available 1/10 production chassis, making drivetrain reliability and throttle control critical.

AdvancedCommercial 1/10 SprintOpen power · Open buggy tires
Official RulesSpare PartsSetup Sheet
The Park Speedway
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Rules Control the Build

This is a preparation guide. Review the current rulebook before buying parts or modifying the car.

Current Rules
Race-Day Mission

Build Legal. Arrive Ready.

Use the Mod Sprint guide to confirm the platform, pack the common failure parts, inspect the car, and preserve a known baseline.

Class Overview

What Is Mod Sprint?

Mod Sprint is the open-power sprint class. Any legal motor and ESC may be used on a commercially available 1/10 production chassis, making drivetrain reliability and throttle control critical.

Legal-Build Snapshot

Rules Summary

ElectronicsAny motor and ESC; tuning and external cooling fans allowed.
ChassisAny commercial 1/10 production chassis; no custom-built chassis.
TiresOpen buggy tires; additives and treatments allowed.
SuspensionAny shocks and shock towers.
BodyUse a legal sprint body and wing configuration for the event.
BatteryLegal 2-cell battery at or below 8.44 volts.
Complete Rules
Class Appearance

What a Mod Sprint Looks Like

These examples show the winged 1/10 sprint-car appearance associated with Mod Sprint: a top wing, open wheels, narrow sprint chassis, and purpose-built sprint front axle layout.

Winged Mod Sprint action photo
Race-Ready Mod SprintA completed winged sprint car on track with the tall top wing, open front axle, and compact sprint layout that define the class.
Mod Sprint chassis example
Platform ExampleA purpose-built sprint platform showing the open-wheel layout, cage structure, and wing mounting that racers look for when buying into the class.
Second winged Mod Sprint action photo
Finished Car ExamplePaint schemes and manufacturer paths can vary, but the finished car should clearly present the winged sprint appearance expected in Mod Sprint.
Use the rulebook for legality. These photos explain the Mod Sprint look only. The completed car still has to meet the current Park Speedway rules for chassis, electronics, body components, tires, and any other class requirements.
Common Starting Points

Platforms & Manufacturers

These are practical starting points, not additional rules.

Common Manufacturer

Custom Works RC

A common manufacturer path for commercially produced open-power 1/10 sprint cars.

Common Manufacturer

Team GFRP

A common manufacturer path for commercially produced open-power 1/10 sprint cars.

Manufacturer choice does not replace the rules. Both Custom Works RC and Team GFRP are common platform options for Mod Sprint. The completed car must still meet every current Park Speedway class requirement.
Common Choice

1

Custom Works RC sprint platforms.

Common Choice

2

GFRP sprint platforms.

Common Choice

3

Other legal commercial 1/10 sprint chassis.

Race-Day Reliability

Recommended Spare Parts

Carry the parts most likely to end a race day after a crash or drivetrain failure.

Parts Worth Carrying

1Front arms, spindles, kingpins, and links
2Rear axle, hubs, transmission parts, and bearings
3Wing mounts, nerf bars, and body mounts
4Shock shafts, seals, springs, and pistons
5Spur gears, pinions, and drivetrain hardware
6Fan, sensor wire, and power leads
7Wheel nuts and multiple tire options
8Chassis-specific crash parts

Build a Parts Box

Keep common hardware, drivetrain pieces, steering parts, and suspension components together in one labeled container.

1Use manufacturer part numbers.
2Test electrical spares first.
3Organize hardware by size.
4Replace bent parts before major events.
5Restock after every race.
Before Technical Inspection

Pre-Race Inspection

A legal car can still lose track time through loose hardware, leaks, or a failed transponder.

Class Check

1Confirm commercial chassis, not custom built.
2Inspect gears, axles, bearings, and motor mount.
3Check sensor wires, fan wires, and solder joints.
4Secure body, wing, and nerf bars.
5Inspect steering, shocks, glue, and wheel nuts.
6Keep the battery at or below 8.44 volts.

Universal Check

1Steering moves freely and returns to center.
2Suspension moves without binding.
3Wheel nuts and chassis hardware are tight.
4Tires are glued and legal.
5Body, battery, receiver, and wiring are secure.
6I-Laps transponder is reading.
Safe Starting Point

Baseline Setup

1Reduce power until laps are repeatable.
2Build a stable balance before increasing output.
3Check drivetrain temperature every run.
4Tune steering and throttle together.
5Record motor, ESC, gearing, and tires.
Use the Tools

Record Before Adjusting

The setup sheet preserves the baseline. The quick tuning sheet gives a small adjustment direction. The Driver's Library explains why it works.

Setup SheetTuning Sheet
Continue Learning

Related Setup Guides

Use the cheat sheet for direction, then open the full guide.

Weight TransferSpringsShock OilRide HeightAlignmentDiagnostic TreeEntryCenterExit
North Vernon Park RC Speedway Tech Center

Prepare the Mod Sprint

Confirm legality, inspect the car, carry common failure parts, and record the baseline.

Official RulesTech CenterDriver's Library
The Park Speedway · Mod Sprint Tech Center