Best Torque Converter for LS Engines

Boss Hog Learning Center

There is no single best torque converter for every LS engine. A stock 5.3 truck engine, cammed 6.0 street car, naturally aspirated 408 stroker, and turbo LS build can all require very different converter characteristics.

Start With the Complete LS Combination

Converter selection should begin with displacement, camshaft, cylinder heads, intake, exhaust, power level, transmission, rear gear, tire diameter, vehicle weight, and intended use. Peak horsepower alone is not enough.

Camshaft Matters

Many LS builds receive a larger camshaft early in the modification process. A cam that moves the useful powerband higher may benefit from additional stall so the engine can reach a stronger part of the torque curve before the drivetrain is fully loaded.

Vehicle Weight Changes the Answer

A 3,200-pound street car and a 5,000-pound truck can behave very differently with the same LS engine and converter. Heavier vehicles generally place more load on the converter and should be evaluated accordingly.

Rear Gear and Tire Diameter

A taller tire effectively reduces gearing, while a numerically higher rear gear increases mechanical leverage. Both affect how the vehicle responds and should be included in converter selection.

Naturally Aspirated vs. Power Adder

A naturally aspirated LS may need a different converter than the same engine with nitrous, a supercharger, or a turbocharger. Power adders can dramatically change the torque curve and converter load.

Street, Street/Strip, or Race?

A street car needs drivability and heat control. A street/strip car may accept more stall in exchange for stronger launches. A race car can be optimized more aggressively around launch RPM and engine powerband.

What Stall Speed Should an LS Use?

The right answer depends on the combination. Rather than choosing a converter because another LS owner uses a certain RPM range, use your own engine, gearing, tire, weight, and vehicle use to determine the starting range.

Technical information is provided as a general guide. Final torque converter selection should be based on the complete vehicle combination and intended use.