High RPM Backfire when fully warmed

TheGrimSpeed said
Plugs I know I’m running rich at start up I have no choke set up, there’s some oil from a valve cover leak I had

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That plug is on the hot side for me. If you are running a timing curve you can increase the initial and reduce the total some.

If it’s locked out you need to pull some timing out of it ASSuming pump gas.