torque converter recommendation needed

Quickdart360, I've used it for 4 years on the street with 3.23 gears and a pump gas 500" motor. It has been great, no problems.
I finally drove it to a track this summer, ran mid 10's and drove it home. It's showing 17.5% slip at the track which I wouldn't want in a drag car but a couple we'll known experts told me it's only because of the 3.23 gears, especially with a stroked big block.