Thread: 355 combo evaluation -dyno? Thoughts, suggestions, comments appreciated

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Jerry Clayton:
You bring up an interesting point. In fact, the fastburn heads came with self aligning 1.6 roller rockers (I think crane made for GM with the bowtie logo). Side note: during mock up of the self aligning jobbers I noticed two of the pushrods were touching the intake runner. Kinda screwy design if you ask me. I went with the big tip scorpions and adjustable guideplates to get the pushrod off the intake runner and keep the valve tip fully contacted with the larger roller tip hanging off one side.

Maybe the thought is the added lift with the inceased ratio rocker does not equate to a substantial amount of added wear. WTF is substantial!
For my application 1.6 rockers equaling .565 lift using the ideal midlift set up calculates to .029" scrub or pattern on the valve tip.
1.5 rockers equaling .530" lift reduces the scrub to .026"
.003" difference is 10% added pattern.

.003" delta or 10% increase seems small but what is the added stress on the valve guide? Beats me... if using behives they claim an increased center hold by design. Seems reasonable to say Behive springs would reduce the wear of the valve guides.

I have no idea what this translates to pushrod to rocker cup wear.

Very interesting point.

I hear a lot about people saying their rig is sluggish due to a low stall. For those that experience this with a similar combo as mine, is it a serious issue or is it that you wanted the rig to jump like a whipped quarter horse? I am trying to justify a lower stall than optimal to balance drive ability.