1. What Is Stall Speed?

Stall speed is the maximum speed at which a torque converter can operate when the output is completely stopped (stalled) while the input is rotating. It's a critical parameter in automotive transmission systems that indicates the torque multiplication capability of the converter.

2. How Does The Calculator Work?

The calculator uses the stall speed approximation formula:

Where:

• \( K \) — K-factor (rpm/√lb-ft), a characteristic of the torque converter
• \( Torque \) — Engine torque (lb-ft)

Explanation: The formula approximates the stall speed based on the square root relationship between torque and the converter's K-factor, which represents its performance characteristics.

3. Importance Of Stall Speed Calculation

Details: Proper stall speed calculation is essential for matching a torque converter to an engine's power band, optimizing vehicle launch performance, and ensuring efficient power transfer in automatic transmissions.

4. Using The Calculator

Tips: Enter the K-factor value specific to your torque converter (typically provided by the manufacturer) and the engine torque in lb-ft. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical K-factor range for torque converters?
A: K-factors typically range from 100 to 250 rpm/√lb-ft, with performance converters having higher values and stock converters having lower values.

Q2: How does stall speed affect vehicle performance?
A: Higher stall speeds allow the engine to reach its power band faster, improving acceleration but potentially reducing fuel efficiency at lower speeds.

Q3: Can I use this calculator for any torque converter?
A: This provides an approximation. For precise calculations, consult manufacturer specifications as actual performance may vary based on converter design.

Q4: What happens if stall speed is too high or too low?
A: Too high stall speed can cause excessive slippage and heat buildup, while too low stall speed may prevent the engine from reaching its optimal power band.

Q5: How is torque measured for this calculation?
A: Use peak torque values from engine dyno tests or manufacturer specifications for the most accurate results.