if its been like that for a year now i wouldnt worry much about it, and yes i believe u can do head studs without pulling the head, doing em one by one. but i have never done em. and im not exactly sure what drive pressure is, mabye someone will chime in
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2007 dodge 5.9 6" lift, 22" mazzi hulk's 37" kumho road ventures. smarty. afe intake, power puck, 8" stacks, sterling grille. 450 hp, 908ft lbs. 14.9 1/4 mile