Well everyone, after 12 years, 7 shops, 637-ish tunes and 3 dyno's it finally happened. I just had a driveshaft let loose on the dyno. And the stink of it is that I finished the tune earlier. The owner insisted on a dyno run video and that's when she let loose. Surprisingly the driveshaft safety loop took most of the brute force and no real damage done.
Car is a 67? fastback with 5.0 coyote swap and mt82 6spd w/ 9" rear and A/C

She is an absolutely beaut. Driveshaft just wasn't up to the task.
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