The specifications for most high-performance torque converters relate dragstrip performance potential, which doesn't help much when selecting a converter for autocross use. Although many of the same considerations apply, autocrossing calls for a somewhat lower stall speed than drag racing. A Corvette set up for autocrossing won't have a drag racing-oriented Corvette's launch capability (due to tires and suspension) so it's usually best to keep stall speed well below an engine's torque peak. Autocrossing also involves acceleration and deceleration, and a tighter converter offers quicker response during throttle transitions.
By The Numbers
If you're not familiar with dragstrip elapsed times and trap speeds, you'll understandably view improvements of a few tenths of a second and 2-3 mph as insignificant. But if you've ever tried to improve your Corvette's dragstrip performance, you know it takes a good bit of effort to cut e.t. by a tenth and increase trap speed by 1 mph. An improvement of 0.30 second and 6 mph is huge; and, as the accompanying chart demonstrates, that's just what the right converter can deliver.