EDIT: I'll just amend my statement now; if you haven't checked out some of the tuning threads over in the tech section, grab a soda, cup or coffee, or a beer and start reading. There are likely over a hundred threads on conditions exactly like what you explain above...guys like rustyratrod, moper, abodybomber, etc are all very knowledgeable and could help you out quite a bit. That being said, check out the tech section and search tuning, or timing, or something related and just check out all the hits you'll get