Rocker arms for 408 build
I think you are basically agreeing with what I have suggested in post #62?
Everything I'm seeing suggests there is a threshold where the upgrade makes sense.
Lift over .525.
High spring load (over 350? not sure.)
High revs, especially continuous.
Desire/need for small horsepower gains.
I am curious to know what you have seen typically breaking.
Also, what would be typical cost to have rollers done to your satisfaction?
Mostly I have seen the fulcrum split wide open, but I've also seen broken adjusters, the tail end broken completely off the rocker, threads ripped out of the rocker body when the adjuster was punched out of the rocker body, broken roller axles, etc. etc.
Rockers aside, you can include dropped valves from locks unlocking, or pulling through the retainers, broken valve springs, valve heads breaking off. Some off these are extreme cases, but any part will break if you take a jackhammer to it long enough. That is the effect of an unstable valvetrain from incorrect geometry.
High quality parts are not immune to a lack of attention to detail. The best NASCAR connecting rods will let a bearing spin and will be destroyed, if there is inadequate bearing clearance. I know what you are saying, "I would never put an engine together without checking bearing clearance". Ok, now replace "bearing clearance" with "rocker geometry". Now we're on the same page.
As far as cost, I won't discuss that here. There are too many variables to consider, so it would be best to call so I can get the information needed to do an estimate.
