Just put those in 4 days ago and when accelerating my car begins to slightly buckle as if I had wet plugs! The spark plugs were changed too. They are denso iridiums. Wonder if it's just the spark plugs. Car has major top end and I don't see how it could have been from the installation of these items but this is the first mod I can actually feel. The plugs are properly gapped at .065! Any help is appreciated!!!