Its hard to guess without knowing a little more info..PAP, axis tilt and axis rotation... Assuming you are a medium high tracker (PAP about 5" over and a little up or down) and neither extreme in axis rotation (up the back or around the side), placing the pin well above the midline (3"to 4"), will help gain extra length. For most spans, this leaves the pin above the fingers some where.. Based upon your rev rate, on heavier oil, I would go with a 4.5" to 5" pin to PAP distance... medium oil a 5" to 6" pin to PAP distance. To get a strong break point, place the mass bias somewhere around 4.5" to 5" from PAP.
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I'm a great quitter. It's one of the few things I do well. I come from a long line of quitters. My father was a quitter, my grandfather was a quitter... I was raised to give up.
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