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Choosing stall speed for a HEMI-powered vehicle requires more than picking a number from a chart. Engine torque, camshaft, transmission, vehicle weight, gearing, tire diameter, and intended use all influence the result.
Why HEMI Torque Matters
HEMI engines can produce strong torque, and that torque affects how a converter flashes. A converter that behaves one way behind a mild engine may act differently behind a higher-output HEMI.
Camshaft Changes the Powerband
A larger cam can move the engine’s useful range upward and may require additional stall to avoid loading the engine below the cam’s effective range.
Street vs. Street/Strip
Street vehicles need acceptable cruise behavior and heat control. Street/strip combinations may benefit from more stall for stronger launches.
Vehicle Weight
A heavy Charger, Challenger, truck, or swapped classic can require a different approach than a lightweight race car.
Rear Gear and Tire Height
Taller tires effectively reduce gearing and can change how the vehicle responds. Rear gear and tire height should always be included.
Power Adders
Nitrous, superchargers, and turbochargers can dramatically change torque delivery and converter needs.
Use Stall as a Range, Not a Promise
Advertised stall is a starting point. Actual stall depends on the engine and vehicle combination.
Use the complete vehicle combination. Engine torque, camshaft, transmission, vehicle weight, rear gearing, tire diameter, power adders, and intended use can all change how a converter behaves.
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Technical information is provided as a general guide. Final torque converter selection should be based on the complete vehicle combination and intended use.