Originally Posted by Zoonhollis

It most certainly is. Boost means nothing if there's not a concomitant increase in fuel delivered. I learned this both by doing it myself, and from Herr Dieseling Doktor (to say nothing of basic chemistry/physics). Do a search if you don't believe me, or look here:

http://www.peachparts.com/Wikka/OM617BoostControl

If the originator of this thread has not done this adjustment, no wonder his car is still sluggish.