1. What is Stall Speed?

Stall speed is the maximum speed at which a torque converter can multiply torque when the output shaft is completely stopped (stalled) while the input shaft is rotating. It's a critical specification for performance vehicles.

2. How Does the Calculator Work?

The calculator uses the stall speed formula:

Where:

• \( Torque \) — Torque applied to the converter (lb-ft)
• \( K Factor \) — Torque converter multiplication factor
• \( Engine Torque \) — Engine torque output (lb-ft)

Explanation: The formula calculates the rotational speed (RPM) at which the torque converter will stall based on the input torque, converter characteristics, and engine torque.

3. Importance of Stall Speed Calculation

Details: Proper stall speed selection is crucial for optimal vehicle performance. Too low may cause sluggish acceleration, while too high may reduce efficiency and cause excessive heat.

4. Using the Calculator

Tips: Enter torque in lb-ft, K factor (typically 1.5-2.5 for street vehicles, higher for racing), and engine torque in lb-ft. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical stall speed for street vehicles?
A: Typically 1800-2500 RPM for most street applications, while performance vehicles may use 2500-3500 RPM.

Q2: How does stall speed affect launch performance?
A: Higher stall speeds allow the engine to reach its power band quicker, improving acceleration off the line.

Q3: What factors influence K factor?
A: Converter design, stator angle, number of fins, and fluid characteristics all affect the K factor.

Q4: Can stall speed be too high?
A: Yes, excessive stall speed can cause overheating, reduced fuel economy, and drivability issues.

Q5: How does engine torque affect stall speed?
A: More engine torque generally requires a higher stall speed to effectively multiply that torque.