I was noticing that my rockers were louder than normal and I was also having acceleration problems below 3K rpm. When I opened up the valve covers I noticed that the bottom of the covers showed signs that the rockers were hitting the covers. I was able to get some covers that clear the rockers. I went and reset all the valve lashes but when I went to restart the car there was white smoke coming from the driver side of the engine. I only cranked the car twice for about 3 seconds each time but the car did not turn over. The exhaust manifold were still cold to the touch. I was wondering if my valves are messed up since the rockers were hitting the covers. Also any clues on what to look for that is causing the white smoke.