the noise you hear from the air box is normal, its caused by cylinder pressure escaping back into the intake and air inlet system past a partially open intake valve after the engine has been shut off. if you are using factory gauge to determine your boost, remember they arent very accurate, to be sure you would need an actual boost gauge to verify
Kenne Bell 2.1 Twin Screw (9 PSI), Kenne Bell Big tube kit, BBK off road x pipe, Flowmaster super 44's, Snow Performance stage 2 MAF Boost Cooler, Walbro 290lph fuel pump, 40A Boost-A-Pump, Steeda tri-ax, 3.73's, Spec stage 1 clutch, Eibach swaybars, tail light sequencers, smoked headlights, LED bulbs 400HP 449TQ as of 10/2015 at the rear wheels. It feels good to be blown.
Last edited by jwog666; 04-13-2016 at 11:34 AM.