Log the timing and make sure somethings not pulling timing.

Also, I used to shift to third during the burnout in one of my past cars (can't remember which) for the same reason, to keep the transmission alive. When I did, I remember I had to start anticipating the shift with my right foot to keep the power up for the shift and to carry it on into third. If your right foot is slow to react to the shift, it will probably seem like it's laying over.