i have a 98 mystique ls 5 spd v-6 and i notice that at 4000 rpm my car gets a major boost...is that a normal thing in these cars and if it isnt what could it be? 
1998 Mercury Mystique LS Dark Blue, Leather, 5spd, Duratec 2.5 L V-6 And Am Currently Ordering A SVT Contour Touring Style Wing, And Still Looking For The Body Kit
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