My Quinn Stallion has a BH of 8" and I've put rubber 'whiskers' at the quarter-nodes of the bowstring. 550 to 680 grain arrows come out with a nice thunk from the D-97 string.
More on the quarter-nodes: I measure the bowstring's length from the contact point at the upper limb to the contact point of lower limb . In my case, this is from brush button to brush button. This length is divided by four & the whiskers are placed at this quarter-point, measured down from the brush button(s).
If you're using cat-whiskers, always remove the cat first, then do the tying-on.