want more power from my 318...

Ok, the intake is the performer. The heads have: 4027168 on the inside and on the other side of the pedistool it has 555 on it. My stall converter is actually a 2500 rpm stall I went and looked up the part # on the TCI website. When I took the valve cover off ov the passenger side head I noticed that one of the rocker arms looked different than all of the others. It was casted metal instead of stamped out like all of the others, and where the pushrod contacts the rocker arm there is an adjustable screw with a place for a wrench to go on it, so you can adjust it. I thought these valves were not adjustable? And it seems to be pretty loose, I can move it side to side approximately 1/4" and up and down approximately 1/16". Is this supposed to be like this?

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