Misfire @ High RPM. Valve float or...???

Wow! Lots of good replies here.
Ok I'm using the springs that came with the eddy heads because I believe they can handle up to 600 lift.

I'm gonna look into the fuel pressure thing too. Like I said I run a Holley black with -8 to the regulator. And a return. I'm using a stock tank without a sump and honestly feel the pump is working harder then in should..but anyways I have a fuel pressure gauge under the hood but it sucks cause it's liquid filled and reads wrong when hot.
I would like to install a fuel pressure gauge up under the cowl so I can read it when I'm at WOT.
As far as battery power I'm using a optima red top.

I have a innovate air fuel gauge and I actually jetted down the car a bit because I felt I was running rich. That being said I'm still in the process of tuning at wot.