Cant stop the Fuel Cut in 1998 Sr20det~!! HELP

[SRfairladyZ]

I have a 98 Sr20det engine and I'm having a problem at high rpm (under load), its at about 5600rpm i get a fuel cut (even at stock boost!!), happend on the dyno, watched my a/f reading rocket to 20 when the cut happends so i know its fuel or ignition being totaly haulted. I'm running the Q45 maf, i tried putting my stock maf in and it did the same thing. Also running a SAFC2, bypassed it, still cut. I cant seem to find the problem. Could not having my speed sensor hooked up cause this fuel cut? Btw this engine is in a 71 240Z using the SR20 engine harness and ECU, painless wiring for the ignition power, fuel pump and ECU power. I tried using a HKS fuel cut defenser, it did stop the fuel cut for the most part but, made me run dangerously lean, and made my SAFC2 go haywire, so i took it off. Please help...
getting frustrated.