[aumoore]

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#3 With pedestal-mount rockers, are guide-plates recommended for hardened pushrods?

If you are using most pedestal mount rockers you will not need guide plates. If you are using guide plates and stock pushrods you may have caused the breakage yourself as the stock pushrods are not ment for guide plates.

Did you set the preload properly when you put the rockers in? With the FMS roller rockers you turn the cap screw down until you just feel resistance while spinning the pushrod with your fingers. You should only be able to further tighten the cap screw from 1/2 to 1 full turn. If more than one turn shims will be required.