For years we got by with two- and three-speed automatic transmissions, but one of the biggest factors in improving driveability was the introduction of overdrive transmissions. While it's possible to pull such a transmission from a junk car, why gamble on its unknown history or mileage, especially when the internals of an auto trans are beyond most hobbyists' capabilities when it comes to repair?
A far better option is to purchase a new or remanufactured trans, tailored to your engine's power output. TCI Automotive offers three stages of transmission: the Street Rodder, capable of handling 350-525 hp, depending on the application; the Streetfighter (400-700 hp); and the Super Streetfighter (up to 1,025 hp). Each is available on its own or as a package with torque converter, transmission cooler, Max Shift fluid, dipstick, and universal TV cable. Though we're installing a 700-R4 GM trans here, TCI Automotive offers a range of GM, Ford, and Chrysler transmissions in Street Rodder, Streetfighter, and Super Streetfighter.
Given that the subject of our install is a mild 350-equipped 1954 Chevy Bel Air custom, the 700-R4 replacing an old TH400, the Street Rodder package was perfect. This offers excellent street performance and durability, TCI Automotive equipping this level of trans with an automatic valvebody and performance kit–equipped valvebody, providing firmer, but not too harsh, shifts, while remaining fully automatic and retaining the stock shift pattern. According to TCI Automotive, “Each Street Rodder transmission and torque converter undergoes the industry-recognized Triple Testing to verify that internal fluid pressures and shift characteristics match strict TCI Automotive quality control standards. Torque converters are tested to maintain that the impeller body and pump drive hub remain true and are then pressurized and tested to confirm the integrity of the weld seams. Finally, each unit is computer balanced to reduce drivetrain vibrations that can cause serious damage to your converter. Transmissions and their internal components are inspected and stock parts are replaced with high-performance TCI Automotive–manufactured parts where applicable. Valvebodies are remanufactured and 100 percent tested prior to installation. Last, each transmission is subjected to both a static hydraulic pressure test during assembly and a final dyno test prior to shipping. That's Triple Tested for your specific application."
We should mention a couple of things before we get into the install. First, the 700-R4 (as well as the 200-4R) uses a lock-up torque converter, and in its factory application, is computer controlled. All lock-up TCI Automotive 700-R4 transmissions have the TCI Automotive Universal Wiring Kit installed and may be wired independently of a vehicle computer. This also allows for easy retrofit into earlier non 700-R4 equipped applications such as this. Secondly, the TV cable setup instructions should be adhered to implicitly, as this is not a simple kickdown cable and incorrect installation will cause transmission failure.
Our application included modifying the transmission mount on the crossmember, as the 700-R4 is 4 15/16 inches shorter than the TH400 from the front of the bellhousing to the rear mount, but that aside, the swap was a bolt-in deal.