fuel cut VS ign cut VS boost leak ?

[Silverbullet]

ok, i have a little situation. My car ran perfectly fine before. Just a few days ago, im expiriencing some type of cut. I figure it is a fuel cut, but im running stock everything so it dosnt make any sense. I'm only runing 7psi with Walbro 255 pump, and Z32 filter. I did some more runs on the highway just now and i've observed this only happens in high RPMs and full boost. It happens anywhere from 4000RPM to redline on full boost so it makes sense to me that its some type of fuel cut. Whats wierd is there is no other symptoms. I dont have idling problems, i dont have stalling out problems, i dont have any hesitation, spuddering, or studdering. Anyone have any ideas? i am stumped. Oh yea, it might possibly be a boost leak or an ign cut, but im leaning more towards this being a fuel cut problem because i dont notice any extra backfire or huge fireballs after my loss of power. I did some searching and most ppl who have identical problem with me ususally have their cars spudder or have crazy idle or something. Mine dosn't seem to do anything else at all.