Interference in RPM in Datalog

[Heyk20]

I've been fighting issues with my car hitting rev limiter early. I looked into the datalogs and my RPM curve looks awful. It always stays around the correct RPM spot, but it varies by 200-500RPM in the top end which causes me to hit ignition cut at 7000 RPM with a 7500 rev limiter. I don't think I'm having any misfiring issues. I have a brand new autozone distributor with an external MSD coil. My plugs are gapped to .020. At about 3 minutes on that datalog, you can see where it goes from 7000 to 7600 instantly. I know the dash isn't super accurate, but I definitely wasn't at 7600. Please ignore the sporadic AFRs this is the first car I've ever tuned and I'm still dialing it in.

[Spunkster]

It may be the distributor, as anything but OEM do not usually work very well. Try borrowing an OEM distributor form a known working vehicle.