I'd yank the valve covers and check for extreme, (and sometimes not so extreme), looseness in any of the rocker arms.
It's quite possible you are a lobe, (or more).
Don't know if you're running a solid lifter, or hydraulic, (you didn't state if I remember correctly), but either way, it's way possible to have 'lost a lobe' of two, either accidentally, or a poop occurs situation.
I highly recommend just running the outer springs during the cam break-in period. Run without the inner springs, for 30 minutes or so, and then shut everything down, install the inners, and re-fire engine.
The last cam we installed in last years motor, was installed in a different motor before that, and it ate a lobe in that application. Had the cam repaired, and installed it in my last years motor, and sure as hell, it ate one, (a different one), that time.
This years motor we ran just the outer springs for the said 30 minutes, then took her apart, and installed the inners for the dyno session. So far, so good.
In either case, good luck, and hope nothing too expensive 'went away' for ya.
Steve
drag79stang
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