I'm thinking I put too small a cam in my 360 Magnum...

@Brooks James
"Thanks, my springs are also the Hughes 1110"

IIRC,
the springs on my 367 are also Hughes 1110s, circa 2004.
And 5003 lifters, set at 1/2 turn preload. and the cam is
HE3038AL .549/.571 @ 1.6 adjustable-arms purchased from Mopar
I shimmed mine up a lil.
This set-up goes to 7200 with ease.

I missed a shift once, a long time ago, and saw the tach needle coming down past 8000.
I let the revs come down to ~3000, then slowly back to idle. BadaBoom all was good! Surprise surprise.
Right after that;
I installed a rev-limiter.......
and slick-shifted Second and Third gears, and
rebuilt my shifter, and
loc-tighted the external levers onto the studs.
After that, don't remember that I ever missed a shift again.