Yet another bow question

I've tried searching for this, but I can't seem to find an answer to this specificly:

Lets say I have this bow:
Piercing Dmg: 15-28 (req. 11 Marksmanship)
Damage + 13%
Energy -5
Marksmanship +1 (18%chance while using skills)


I know that a bowgrip controls the marksmanship line and that I could replace that with another.
But what about the "Damage + 13%" line? I figure the "Energy -5" is a counter to the 13% at all times for balancing it out?
Is there anyway to replace these two lines with say "+15% while health above 50%" with a rune or something, or is that line always predetermined by the bow?
Is it possible to add runes to a bow at all, or is it only bowgrip and bowstring?

Oh, and about the Poisoner's bowstring. Is it always perfect in lengthening the poison duration with 33%, or might it not be perfect as lets say a bowgrip of defence which can be armor +4 or 5?

You cannot change the inherent damage properties of a weapon (e.g., +13%, 15-28, etc.). You can add a string that, in the case of elemental strings, changes the type of damage dealt. You can also change the properties given by a grip, as you noted above.

Like the elemental strings, poisoner's strings are one type and one type only. There are no "better" poisoner's strings. The only strings that have variables are sundering (1-10% chance of 10% penetration) and vampiric (range from 5:-1 (best) to 1:-1 (worst)).

Thanks for the fast answer! It is as I thought.

I'm thinking I should just try to find my desired bow(s) clean with Max Dmg and +15% while health above 50%, and then add the bowgrip and and string that fits my needs.

Are there any other inherent bow features I should look for than those two?

What about zealous? Is there a range?

There is no range for zealous upgrades. It's always 1/-1.

zealous strings don't steal energy when u hit an enemy.... right?

Um, that's exactly what they do. You have -1 Energy Regen, but they steal 1 energy from the enemy every time an arrow hits.

Zealous is one of those things that really is really player specific. Not everyone likes them, but they are better for Rangers who use alot of Preperations

hmm.. never thought of it... i knew vamp strings stole HP... lol... don know why i didn't think of zealous strings not stealing energy