TH350/400 11in Torque Converter

The TH350/400 11in Torque Converter from TCI is a purpose-built transmission component engineered for street and strip applications where consistent power delivery and engine efficiency matter. Whether you're upgrading a vintage muscle car, modernizing a classic hot rod, or tuning a performance truck, this 11-inch converter replaces the factory unit to unlock higher stall speeds and improved throttle response. Torque converters are the hydraulic coupling between your engine and transmission—they control how early your engine can load the drivetrain, making them critical for launch characteristics and overall drivability.

TCI's engineering focuses on flow dynamics and clutch pack design to optimize fluid coupling efficiency while reducing heat generation and slippage during acceleration. The 11-inch diameter is the industry standard for TH350 and TH400 transmissions, fitting directly into existing bell housings without modification. Higher stall-speed converters allow the engine to climb RPM before the transmission locks, maximizing torque multiplication off the line—ideal for vehicles with aggressive cam profiles or turbocharged engines that need time to build boost. The unit weighs 26.41 lbs and is constructed with precision-balanced components to minimize vibration and extend clutch pack longevity under repeated loading cycles.

Buyers should verify their current transmission model—TH350 and TH400 converters are not interchangeable with newer overdrive transmissions or early versions without proper dimensional confirmation. This converter suits enthusiasts rebuilding transmissions, performing top-end engine upgrades, or swapping powertrains into custom chassis where transmission efficiency directly impacts acceleration and fuel economy. Professional installation in a transmission shop ensures proper core sampling, fluid selection, and cooler line setup for optimal performance and longevity in both street and racing environments.