FTI Performance TH400 Level 4 Transmissions TH400-4K21

Overview FTI Performance TH400 Level 4 Transmissions TH400-4K21 Brand: FTI Performance Manufacturer’s Part Number: TH400-4K21 Part Type: Automatic Transmissions Product Line: FTI Performance TH400 Level 4 Transmissions Summit Racing Part Number: FTI-TH400-4K21 UPC: 887753824790 Number of Gears: 3 Bellhousing Bolt Pattern Manufacturer: Chevy Transmission Shift Pattern: Reverse Valve Body Style: Full manual Transmission Advertised Horsepower Rating: 900 Torque Converter Included: Yes Flexplate Included: No Transmission Controller Included: No Wiring Harness Included: No Transmission Cooler Included: Yes Advertised Flash Stall Rating: 3,400–3,800 rpm Trans-Brake Included: Yes Lockup Compatible: No Transmission Pan Style: Deep Transmission Pan Material: Aluminum Transmission Pan Finish: Natural Yoke Style: Slip-on/bolt-on Input Spline Quantity: 30 Input Shaft Material: Hardened steel Input Shaft Style: TH350/400 First Gear Ratio (Automatic Transmissions): 2.43 Clutch Hub: Billet Steel Transmission Case Style: OEM Transmission Case Material: Aluminum Transmission Case Finish: Black Transmission Shield Built In: No Flexplate Shield Built In: No Fluid Fill Location: Case Transmission Fluid Included: Yes Transmission Fluid Quantity Included: 12 qt. Dipstick Included: Yes SFI Rating: SFI 4.1/30.1 Remanufactured: Yes Quantity: Sold as a kit FTI Performance TH400 Level 4 Transmissions Overview The FTI Performance TH400 Level 4 Transmission TH400-4K21 is a complete, race-ready transmission system engineered for serious performance enthusiasts. Designed to handle up to 900 horsepower, this kit delivers exceptional strength, precision shifting, and reliability for high-demand applications. As a result, it provides everything needed for a powerful and consistent drivetrain setup. Performance & Components In addition, this package includes a billet torque converter with a 3,400–3,800 rpm stall rating, optimized for aggressive launches and improved track performance. The integrated trans-brake and full manual valve body offer precise control, allowing drivers to maximize reaction times. Because of this, racers benefit from quicker launches and more consistent results. Advanced Engineering Moreover, the transmission features high-performance clutches and steels, a 34-element intermediate sprag, and a high-flow pump to ensure durability and efficient operation. The race-prepped case, billet forward clutch hub, and heavy-duty components further enhance strength under extreme conditions. For this reason, it is capable of withstanding repeated high-stress runs without compromise. Applications & Benefits Finally, this complete kit includes essential components such as performance ATF, a locking dipstick, and a full cooler system, simplifying installation and setup. Suitable for drag racing, street/strip builds, and high-powered vehicles, it offers versatility alongside performance. Ultimately, it delivers a comprehensive, high-performance solution for drivers seeking durability, control, and race-proven reliability.