Upgrading Torque Converters

If your vehicle is pre-'90s and has an automatic transmission, chances are it could really benefit from a modern performance torque converter. In its quest for more efficiency and performance, the auto industry has put an incredible amount of research and development into torque converters. The result is torque converters that provide much more torque multiplication (more on that later) and higher efficiency. These benefits are available for your older vehicle and will literally transform the way it drives and performs.


Old-style ('50s-'70s) torque converters rarely failed so car owners gave them little thought. Failures were usually caused by rocking a car from drive to reverse trying to get unstuck in the snow, or overheating the trans by towing thereby wiping out the phenolic bushings and washers found in stock torque converters. Another cause of torque converter failure is when the engine's horsepower is increased without installing a performance torque converter that has been fortified for the extra power. Lock-up torque converters introduced in the '80s and used in virtually every automatic transmission today were prone to clutch failure early on, but most of those problems have been resolved.

When to Replace
How can you tell if your torque converter needs replacing? Some sure signs are metal contamination in the transmission fluid. A loss of power or a loss of stall speed (the rpm at which a converter slips when you step on the gas). A torque converter may make a grinding noise from internal metal-to-metal contact when clearances go away. Basically, if your transmission fluid has been cooked several times or the transmission has failed sending debris into the converter, then it's time for a rebuilt converter. Expect to fork out $150-$250 for a standard rebuilt replacement converter.


For an additional $200-$400 you can replace your present torque converter with a modern performance converter and gain the performance benefits plus durability that is unavailable in OE replacements. And it's the perfect resto modification. It can't be detected by any show judge and the vehicle can always be returned to original by installing the OE converter (not that anyone would want to).

What to Expect
Okay, what do you get for your $450-$650 dollars? Depending who you purchase the torque converter from, this is what you should get. A modern converter core (virtually all torque converters are rebuilt from existing OE cores). Early torque converters from the '60s typically had a 1.7- 1.9-torque multiplication factor. What this means is that if your engine produced 200 lb.-ft. of torque at the converter's stall speed, it would multiply it by 1.7 providing 340 lb.-ft. of torque to the driveshaft. A typical modern torque converter has a torque multiplication factor of 2.5, so just changing to a modern design with the same stall speed would bump the torque from 340 lb.-ft. at the driveshaft to 500 lb.-ft. without touching the engine.