Comp Cams Xtreme Energy
I have some noise with the XE268H cam I have in my 360. I have magnum heads and Comp did not have a spring & retainer for this head. The comp tech line indicated that the Mopar Performance Magnum R/T spring would be suitable. I am also using Melling lifters.
I get some lifter clatter when the engine first starts after sitting over night that lasts a second or two. After that I get a very slight ticking at idle that has people asking if it's a solid cam. I do not notice any noise as the rpms rise.
I never got around to measuring lifter pre-load and after putting the engine together Ii was told that with magnum heads and lifts over .5" you need to check to make sure the push rods aren't hitting the heads. I will be checking these items this winter.
Pretty much everyone on this list plus Comp's tech line told me that the XE series cams tend to be noisier and the fact that I have 1.6:1 ratio rockers will make it worse.