pullies are controversial so you can do a search for all the feedback, but unorthodox has the best gains but MIGHT cause problems. AEM
doesn't remove the harmonic damper but doesn't provide as much Performance.
flywheel choice depends on your goal. you don't really want too light unless you plan on a lot of drag racing (and a clutch to match). fidanza is popular but personally i'm gonna go with TRD
. there's tech info on flywheels, also.
the most popular and best all around header right now is trial's. it's also the most expensive. dc is about to release their header with rumored gains at least equal, if not better, to trial. dynoes will prove that (which is why they may be taking longer than anticipated).
the best thing is to search the site (or others) for the best answers. beats waiting for responses...