Great post Denny. Most fellows don't think about long slot rockers until things get all jammed up and it gets expensive. A fellow might be able to simply change to +0.050" keepers to extend the tip of the valve enough to use guided rockers and keep the rocker rails off the retainers/keepers through the entire valve lift sequence. I know I've seen conventional stamped steel rockers with extended slots and rails offered by someone, but I can't remember who. Crane makes a nice "Nitro-Carb" stamped rocker for those of you who want a precision ratio in a conventional rocker.

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