Hydraulic roller cam and stock rocker arms

BigBlockMopar said
I think most folks run with too much (or the recommended) lash which hammers the rollers to bits.

With roller cams I always check/set what the cam-maker thinks the lash should be, and then after hearing the engine run (warmed up ofcourse), I decide how much quieter I want the valvetrain to be, and tighten up the lash accordingly.

I always tend to think cam-makers spec their lash on the loose side so they are safe and it won't cause issues for folks who happen to run their engine at very hot temps occassionally.

Important thing to remember is that the hotter the engine gets, the more the block and heads expand, thus lifting the rockers away from the cam and increasing the lash. This is especially true with aluminum heads and blocks. The cold lash on an aluminum head and iron block should start at .006" tight and an aluminum head and aluminum block should start at .012" tighter cold lash than the recommended hot lash.