Summit Racing Torque Converter Calculator

Torque Converter Stall Speed Equation:

\[ \text{Stall Speed} \approx \sqrt{\frac{HP}{Weight}} \times K \]

Estimated Stall Speed:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Torque Converter Stall Speed Equation?

The torque converter stall speed equation estimates the RPM at which a torque converter will allow the engine to reach maximum torque multiplication. This is a simplified formula used in Summit Racing tools to approximate stall speed based on horsepower and vehicle weight.

2. How Does the Calculator Work?

The calculator uses the stall speed equation:

\[ \text{Stall Speed} \approx \sqrt{\frac{HP}{Weight}} \times K \]

Where:

\( HP \) — Engine horsepower
\( Weight \) — Vehicle weight in pounds
\( K \) — Dimensionless constant (typically ranges from 1800-2500)

Explanation: The equation calculates the approximate stall speed where the torque converter allows maximum torque multiplication based on the power-to-weight ratio of the vehicle.

3. Importance of Stall Speed Calculation

Details: Proper stall speed selection is crucial for optimal vehicle performance. A correctly matched torque converter improves acceleration, towing capability, and overall drivability by allowing the engine to operate in its optimal power band.

4. Using the Calculator

Tips: Enter accurate horsepower and vehicle weight values. The K constant typically ranges from 1800-2500, with higher values for performance applications. Consult torque converter manufacturer recommendations for specific K values.

5. Frequently Asked Questions (FAQ)

Q1: What is torque converter stall speed?
A: Stall speed is the maximum RPM an engine can reach with the transmission in gear and the brakes applied before the drive wheels begin to turn.

Q2: How do I determine the correct K value?
A: The K value depends on torque converter design and application. Street performance converters typically use 1800-2200, while racing converters may use 2200-2500 or higher.

Q3: What factors affect stall speed selection?
A: Engine torque curve, camshaft profile, vehicle weight, gear ratio, tire size, and intended use all influence optimal stall speed selection.

Q4: Can I use this calculator for all vehicles?
A: This provides an estimate for typical automotive applications. For specialized vehicles or extreme conditions, consult with torque converter manufacturers.

Q5: What happens if I choose the wrong stall speed?
A: Too low stall speed reduces performance and may cause lugging. Too high stall speed reduces fuel efficiency and may cause excessive heat buildup.