Frequently Asked Questions

Our quarter mile calculator uses proven drag racing formulas that are accurate within 2-3% of actual track performance. The accuracy depends on:

• Accurate horsepower and weight inputs
• Proper atmospheric conditions
• Vehicle setup and driver skill

Use our density altitude calculator for atmospheric corrections.

We recommend only trusted turbo brands with proven track records:

• 🧰 Budget Tier: VS Racing - Great value with solid performance
• ⚙️ Mid-Level: Forced Performance - Proven track performance
• 🏁 Pro-Level: Forced Inductions - Professional racing grade

Our turbo sizing calculator automatically recommends twin turbos above 85 lb/min airflow for better response and reliability.

Fuel injector sizing depends on your target horsepower and fuel type:

• Gasoline: ~0.5-0.6 lb/hr per HP
• E85: ~0.65-0.78 lb/hr per HP
• Methanol: ~0.9-1.0 lb/hr per HP

We recommend Bosch EV14 series for budget builds and Injector Dynamics for premium applications. Always confirm ECU compatibility before purchase.

Weather has a significant impact on drag racing performance:

• Dense air (cold, dry, low altitude): Better performance
• Thin air (hot, humid, high altitude): Reduced performance
• Density altitude: Can affect ET times by 0.1-0.3 seconds

Use our weather guide to understand atmospheric effects on your runs.

The difference is drivetrain losses:

• Crank HP: Engine power at the flywheel (dyno measurement)
• Wheel HP: Power delivered to the ground (chassis dyno)
• Typical losses: 12-15% manual, 15-18% automatic

Read our detailed guide on converting crank HP to wheel HP.

Gear ratios significantly impact acceleration and top speed:

• Shorter gears: Better acceleration, lower top speed
• Longer gears: Higher top speed, slower acceleration
• Optimal shift points: Usually 200-300 RPM below redline

Use our gear ratio calculator to find your optimal setup.

Trap speed is a more accurate measure of engine power:

• ET times: Affected by launch, traction, and driver skill
• Trap speed: Primarily determined by engine power
• Consistency: Trap speed varies less between runs

Learn more in our article about trap speed vs horsepower.