going crazy !!!!!!!!!!!!!!!

[5ohCOUPE]

My car will run good sometimes and sometimes it will run like crap. Within a second it will be fine then go to crap. It feels like that there is no timing, very sluggish. But a second later it will run good. I have good fuel pressure, new plugs, cap rotor wires. New o2 sensors. It doesnt matter if it is wide open throttle or not. Also there are no codes stored. It seems that there is two different motors in this car and the car decides to pick what one it wants to use. A stock motor or the one that i have in it. I have no idea what is going on. Never had this happen to it before. Any ideas ?????

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91 LX COUPE, 3.73 gears, 2 1/2 inch full exhaust, 1 5/8 shorty headers, 73 MM C&L MAF, 70 MM MAC TB, LUNATI cam, Windsor jr heads, GT 40 intake with ported lower, world class T5 with PRO 5.0 shifter, Griffin aluminum radiator, Fluid Damper, SSM traction bars, 150 HP shot N2O kit, 190 GPH in tank fuel pump with Paxton T-Rex external pump. And more to come.
BEST TIME ON BOTTLE---11.51 @123
BEST TIME ON MOTOR---12.63 @109