sanitarium16

My car was perfect up until a few weeks ago. My car is modified with the following: Mac CAI, FRPP 70mm Throttle Body, BBK Intake Plenum, FRPP PI Intake Manifold, Mac Off-road h-pipe,Flowmaster super 40 catback, Trans-go shift kit, Pro-m 85mm maf, Diablosport predator tuner premium fuel tune.
I have my rear o2 sensors shut off via the predator tuners so i am not throwing any codes or CEL. All 02 sensors were replaced with Bosch last year and the car has brand new plugs, wires, MAF sensor,IAC,cleaned the EGR Valve, cleaned throttle body and new fuel filter. Using the diagnostics feature of my diablo predator i am able to read multiple things. My tail pipes are black with soot and have always been since i put on the off road h pipe. My 02 sensor readings fluctuate from 0.1 to 0.7. I was told this is normal. My MAF voltage is .76 idle. My idle is jumpy....goes from 620,650,700 and fluxuates in between there. There is no pinging or detonating going on that i can hear and i fill up on 93. Do i have to buy a new h-pipe with high flow cats in order to fix this problem? Another note is that my spark advance is jumping around too. 17 to 18 to 19 at idle. I have it raised a little (8% throughout entire rpm range) but i have always had it on this setting. Another thing to mention.....there are no vaccum leaks...sorry for the long post but im trying to be as detailed as possible.