I Have Used Comp. XE Series Cams In Several Builds (Prob. 6) And Every One Of The Had A Slight Tic From The Valve Train To Some Degree. The First Was A 340, After Re-Checking Pre-load, I Changed From The Stamped Rockers To Some Crane Iron's And It Helped Alot, But Still There. (Stamped Rockers Are Like Minature Cow Bells From Harmonics) The Valve Train Noise Is Just The Characteristics Of The XE Series Cam. Oune You Accept That, You Get Comfortable Hearing It, The Cams Work Pretty Well.