Im running a racepack with two O2's, one in each side of the exhaust. Its a F.A.S.T. car with full 2 1/2 inch exhaust, 429SCJ iron intake fully massaged internally. The left side of the motor runs 12.8 to 13.2 while the right side runs 11.6 to 12.0. I've had racepack test and re calibrate both O'2 and they claim they're right on. I can only assume that the design of the intake is the cause. Any ideas on the cure?