it was a cold day and i wanted to see how rich the car is running so i can adjust with the afc or try to with my ear...anyways when i hit 6.5-7k rpm the boost creeped to like 20 psi but only does this once in a while its currently set with a homemade MBC at 17.5 psi i was wondering how it crept any things i should check any help would be great..remember i am new to all of this stuff//thanks