Has to have 40%IAS on Wep for Max WW Speed. So choose ur RW throughout IAS restrictions (was that proper english? ; )) .
U should also get ~100% CB (Crushing Blow). It makes Boss killing much faster, so maybe u have to use Diva Ring.
Helm may be Prowess in Battle RW, dunno if Fana affects WW, but i think it doesn't.
Maybe u understand this Speed Calc although it's in German:
http://www.chaos-sanktuary.net/index.php?id=164Some Translations for u:
Geschwindgkeit - Speed
Frequenz - Frequency
Waffen-IAS - Weapon IAS
Fertigkeit - Skill
Wirbelwind - Whirlwind
Armor should be tempered with RW (for Leech) or maybe Shadowtrick for more Runspeed.