There are alot of people running the Comp 274 and bigger in the 5.7 and 6.4. The factory cars are not going solid roller, I don't think the knock sensors would like it. Maybe try another forum or contact a shop that specializes in the modern hemi.

My 5.7 in my ram is a bit tappy for a few seconds sometimes on start up. My 6.1 has never made a sound, I use 5w40 in it.