Just my opinions:
I make my own furled leaders from fluorocarbon mono and on my 4 weight I would use a 7' furled leader made from 4 pound fluorocarbon and attach at least 5 foot of 4 pound fluorocarbon for tippet.
On an 8 weight rod I would use a 7' furled leader made from 6 pound test fluorocarbon and attach at least 5 foot of 6 pound fluorocarbon for tippet.
The above is just what I would do.
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Warren
Warren
Fly fishing and fly tying are two things that I do, and when I am doing them, they are the only 2 things I think about. They clear my mind.