It also depends a lot on usage, setup and tires. For example, I run a pretty warm 496 and 5 speed with older style Schumacher thru bolt poly mount on the driver side and regular poly on the pass side. The car is set up for road race and gets used that way... including HSAX with standing starts. With 200 TW "handling" tires no issues with either mounts, clutch or the 8.75 rear.

If I put slicks on it and made hard launches on a prepped drag track, probably a different story. I don't know what would break first between engine mounts, clutch and rear end but I am pretty sure one or all three would let go pretty fast.