need new lifters...

Which cam? Typically, because of ramp speed and spring requirements, anything larger than the XE268 will use a lifter that tends to be noisier, and needs a different (less) preload. They are the anti-pump up type, and you will prossibly hear them even if they are working and preloaded right. It sounds a lot like a bad standard lifter. But not quite as loud. Also, roller rockers, and aluminum valve covers can make them sound even worse.