upping line

I will be getting my new line and reel this weekend.  Salmon tapered Cortland.  Is it worth it to up 1 size to a 9 wght line on 8 wgt pole. The reel is an 8,9,10.  Also what does upping accomplish and is the line thicker, heavier??????

I have noticed when I bump up a weight they cast are a lot smoother well at least on the rods I use. All in a personal preference

the heavier line will load the rod faster for up close work, i personaly try to avoid that, and help in roll casting with heavy flies or added weight.
it will turn the casting to mush if you have more than 25 feet or so of line in an overhead cast.
its all about what you want out of it.
 

Remember heavy line because of its thickness creates more drag.  Too much drag will hinder your nymph presentation.

I don't know TB. If your not sinking the fly line and throwing line upstream its disadvantage toward hinder may be fatigue more then diameter drag. All fly lines are pretty fat at that stage so to me a one up doesnt create any more drag the one down. It does however get heavy throwing more rope and mending.

Really think its a better cast advantage to up one. IMO .
The real advantage to me comes at a price ..

P.S.
Avoid dark olive.
I'm good with lime , tan or peach. Sadly I'm not a natural and like eye contact with my line

Since 90% of most fly rod lines are now med. fast, I'll assume your rod is that taper. I'll also assume that the Cortland S/S line in similar to the other 3 companies lines  I've used, and it has a short head that transfers into a heavy belly quickly for roll casting purpose.  Overlining will not overburden the rod. Short roll casts will be made easier, and handling weight in close. Mending over 20' of line will be made harder, as the tip has to move more weight and resistance.  In the end the overlining probably suits your purpose better. I have several 8 wt. lines which I fish on my 7, 8, and 9 wts.   They do fine on all of them.  Small adjustments in casting make a great deal of difference.   As far as turning over weight: some people recommend using a straight leader of 10 pound test, but this will have a hell of a time transferring energy along its length and getting weight flipped.  Better to use a tapered  leader  and step it down to your tippet. Incorporating some small hauls into your cast can make a world of difference. They really can help load the rod.  If you're worried about stealth, lengthen the leader- they give you 15' on the SR. Makes a big difference sometimes.  There's also lots of techniques for getting down fast without using tons of weight.   If you look at discount online fly shops like Sierra Trading Post or Madison River Fishing Co., you can occasionally find these lines at 1/2 price. The  sharp rocks and nasty fish of the SR  beat the crap out of lines quick.  I buy discount or used. 
 
Charlie
 
 
 
 
 
 
 
 
 
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