So it does it parked in the driveway as you bring the rpm up? If so, drop your fan and alternator belt and test it to make sure it’s not an accessory, I had a very bad vibration I was chasing and it turned out to be the alternator
The alternator is new and all the pulleys are March performance. Since this issue was present after the first build, and everything but the torque converter and flexplate has been replaced, I find it hard to believe it is something else.
