![]() ![]() ![]() The heavy-duty case and bellhousing not only provide durability, but also eliminate the need for a transmission shield, blanket, or flexplate shield. When choosing a lock-up converter for an ultra-high horsepower, heads-up type drag race application, it’s mandatory that an aftermarket, SFI-approved Powerglide, or Turbo 400 transmission case and accompanying bellhousing are selected as well. Many racers have recorded significant improvements after switching to a lock-up converter. Shortly after the car is launched, the lock-up clutch is activated by a solenoid at the desired time, eliminating converter slippage, thereby reducing elapsed times and increasing miles per hour. ![]() “During initial development, some manufacturer’s units took well over a second to apply but we’ve reduced it down to as little as 0.3 seconds”, according to Caine. “Lock-up converters have truly evolved”, stated Caine. David Caine of ATI states that improving the durability of the multi-disc lock-up clutch and reducing engagement time has been critical to the success of the units. A wide variety of units are available for most popular late model muscle cars including the Ford Mustang, Dodge Challenger, Chevy Camaro, and Corvette.Īlthough lock-up converters have been used sporadically in drag racing for many years with varying degrees of success, advancements in technology combined with the popularity of Pro Modified and other heads-up classes have helped drive their popularity. These replacement units are truly street worthy and effectively create a “best of both worlds” scenario where the converter has a higher stall speed than the OEM unit, yet without the slippage that is typically associated with a traditional high stall converter. Since the vast majority of late model, automatic transmission-equipped muscle cars are fitted with lock-up converters as they roll off the showroom floor, manufacturer’s including ATI Racing, Hughes Performance, TCI Automotive, and Transmission Specialties offer direct replacement, high-performance units that deliver increased acceleration and quicker elapsed times through higher stall speeds, while retaining their OEM lock-up functions. The auto makers continued to refine their converters over the years, eventually upgrading many to a multi-disc lock-up design for improved function and durability. General Motors followed with their own version the following year with the release of the Turbo-Hydramatic 200C transmission, essentially a TH-200 with lock-up converter functions added. It subsequently eliminated slippage between the engine and transmission when the vehicle was up to speed, reducing engine RPM’s slightly and improving fuel efficiency. The converter would then unlock when the vehicle slowed or if kickdown was activated. Chrysler’s version employed a hydraulically activated single-disc clutch within the converter that applied once the vehicle was up to speed, locking up the converter to provide a 1:1 mechanical connection between the engine and transmission. However, priorities began to change in the mid-1970’s due to the push for increased fuel efficiency and Chrysler followed with a modern version in 1978. It wasn’t long before the domestics were debuting smaller, lighter cars with computer-controlled engines and transmissions, electronic fuel injection, automatic overdrive transmissions, and lock-up torque converters, all with the intent of improving fuel efficiency.Īlthough Packard and Studebaker had pioneered the first lock-up torque converter in 1949, it was discontinued shortly thereafter due to the added cost and complexity. The trying times reduced the demand for large, fuel-thirsty cars and made smaller, fuel-efficient imports more appealing, forcing domestic auto makers to make significant improvements in fuel efficiency. The OPEC oil embargo that began in 1973, with its resulting fuel shortages and soaring gas prices, certainly doesn’t bring back fond memories to those old enough to remember being a part of the endless lines of cars leading to the local filling station. From daily drivers to drag cars, lock-up torque converters have changed the industry. ![]()
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