What is the best way to break in new roller cams? Im runing strait 40 wt. oil how should I run these motors for the first few hours???

True mechanical roller cam doesn't need any real sort of breakin BUT the valve springs (if there new) need to be broken in.Biggest thing is making sure the oil is warmed up before rpm'ing them hard. If possible try to heat cycle them from warmed up to room temp a few times so they can take a "set"(i doubt anyone really does this).It would be wise to check valve lash before putting her to the wood.Avoid extended idling as it kills roller lifters. Changing the oil soon after first run might be good insurance after having motor apart,Smitty

Carney
You trying a go faster cam?