Originally Posted by 03SSLE

A little after the fact, but you should always replace the lifters, springs, retainers and locks when you install a higher lift cam in a previously stock engine. The additional lift of the new cam may be all it takes to break a worn, fatigued spring. BTW - did you check for spring binding at full lift? You ever see the cylinder wall of an engine that dropped a valve? It's not a pretty sight. The majority of the time the scoring on the walls is so bad the engine is basically a paper weight. Another reason to replace all of the above is it also gives you access to replace the stem seals. Again, the higher lift cam will elongate the (old, worn) seals (and wear out the guides) and the engine will start burning oil.