Originally Posted by Youngblood
Grizz... you have two suspension lines so you increase it on both suspension lines. 7" on one plus 7" on the other equals 14" of total suspension line for every 12" increase in the span. There is a doubling effect in there with marking and centering, I have synchronized the length adjustments of the two suspension lines.
Units always help. You're adding 7" per end per foot of _total_ additional span, whereas my units were 7" per end per foot of additional span _per end_.