Martinsville Speedway (0.526 mi) 12° Banking • Concrete Corners

Short track late model stock race: ValleyStar Credit Union 300 sprint simulation

Speed 0.0 MPH
Gear 3RD
Tire Grip 98%
Gap to Leader +0.142s
TRACK ZONE: FRONT STRAIGHT TURNS 1-2 (CONCRETE) BACK STRAIGHT TURNS 3-4 (CONCRETE)

Lap Telemetry Curve (Speed vs Brake Zones)

Speed (MPH)
Brake Pressure
Throttle %

The Science of the Martinsville Paperclip

Threshold Braking in the Turns

Martinsville features two 800-foot asphalt straights flanked by ultra-tight 12° banked concrete turns. Stock cars decelerate from 118+ mph down to 55 mph in under 2.5 seconds. Locking front rotors pushes the car into the outside wall; too much rear bias causes an instant spin.

Concrete vs. Asphalt Transition

Unlike all-asphalt ovals, Martinsville pours concrete in both turns to withstand tremendous braking friction and tire scrubbing. The friction coefficient jumps as cars compress into the corner, requiring smooth trail-braking down to the flat inner curbing.

Lap 175 Race Break Strategy

Late Model 300 races feature a scheduled competition break (Lap 175) for tire changes and chassis wedge adjustments. Drivers who burn off right-rear tires in the first half struggle on restarts. The "bump-and-run" is executed by diving under the leader at Turn 3 apex.

How to use this simulator and tune your car for the fastest lap time

1. Steering & Throttle: Use keyboard Arrow keys or W/A/S/D (or the on-screen pedals). Build straightaway speed to 115+ MPH.
2. Turn Entry: Brake firmly as you reach Brake Marker 2. Do not steer aggressively while 100% braking or the car will push wide.
3. Apex Roll: Release the brake smoothly ("trail-brake") as the car transitions from asphalt to concrete curbing in Turn 1/3.
4. Corner Exit: Squeeze the gas pedal gently off the turn. Too much throttle with low wedge will cause wheelspin and burn off tire life.
5. Download Data: Completed laps populate the Stint Lap Times table. Click "Download Telemetry" to save high-frequency CSV logs with speeds, brake inputs, and sector splits.

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