Ihave an 88 pacifica 2.2 T1. Idle turbo vac.is running 5psi. Accel before shift 14-15psi boost, shifts before cut out. Itis not shifting right, suggestions... Right now running open exhaust. If I put the cat backon and muffler will that change for the better? Do I need the cat? Also isn't there a stabilizing bracket from the fire wall that attaches to the motor, mine is not attached? Thanks>>>