I’m just assembling the top end of my 408 rebuild and have a question on the rocker arms. I’m running 4v closed chamber heads. It also has a comp cams small base circle roller cam with .589 and .617 lift. The valve springs are 140 lbs at the seat and 400 lbs open. I planned on using a Crane retro rocker arm kit that doesn’t require machining the pedestals that I had sitting around. I used one on another Cleveland engine before, albeit on a milder cam without any problems. Recently someone told me that the Crane setup isn’t up to those spring rates. I hadn’t heard that and just wondered if any of you had any experience here. If the Cranes are too weak, how about the Yella Terra’s? I’ve heard good things about them. Any help would be greatly appreciated.
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