When the car is first warming up, I get vibration when revving. Say up to 3k, car feels like it's shaking apart.

After it's warmed up and good to go, I feel almost no vibration from revving or anything.

From what I've gathered from perusing former owner receipts, a fairly recent tranny mount was added that was a stiff competition mount.

Would this be the cause of it, and not the tranny mount being bad? (Or, perhaps, the tranny mount isn't broken in?)

Thank you!

 

Trans mounts don't need a break in period. You will feel slight vibration in the Trans if you have a comp mount not in the motor.

Is the whole car shaking? I know that multiple misfires are common when it warms up.

 

Could be misfires, as it definitely has a misfire issue while warming up. I'll know more Saturday.

 

sounds good