Calculate Torque Converter Stall Speed

Stall Speed Formula:

\[ Stall = K \times \sqrt{HP} \]

Stall (rpm):

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1. What Is Torque Converter Stall Speed?

Stall speed is the maximum engine speed at which a torque converter can hold the vehicle stationary under full throttle. It represents the point where the torque multiplication is greatest before the vehicle begins to move.

2. How Does The Calculator Work?

The calculator uses the stall speed formula:

\[ Stall = K \times \sqrt{HP} \]

Where:

\( Stall \) — Stall speed in revolutions per minute (rpm)
\( K \) — Torque converter constant (varies by converter design)
\( HP \) — Engine horsepower (hp)

Explanation: The formula calculates the maximum rpm at which the torque converter can multiply torque before the vehicle starts moving, based on the converter's design constant and engine power.

3. Importance Of Stall Speed Calculation

Details: Proper stall speed selection is crucial for optimal vehicle performance. It affects launch characteristics, acceleration, and overall drivability. Matching stall speed to engine torque curve ensures maximum power transfer.

4. Using The Calculator

Tips: Enter the torque converter constant (K) and engine horsepower (HP). Both values must be positive numbers. The K value is typically provided by the torque converter manufacturer.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical K value range?
A: K values typically range from 1800-2800 for street performance converters, and higher for racing applications.

Q2: How does stall speed affect vehicle performance?
A: Higher stall speeds allow the engine to reach its power band quicker, improving acceleration but may reduce fuel efficiency at low speeds.

Q3: Can I use this calculator for any vehicle?
A: This formula works for most automotive torque converters, but specialized applications may require different calculations.

Q4: What factors influence the K constant?
A: The K value depends on torque converter design, including stator angle, fin count, and internal clearances.

Q5: How accurate is this calculation?
A: This provides a good estimate, but actual stall speed may vary based on vehicle weight, gearing, and other factors.