The exhaust manifold porting is (imop) a must, either do it yourself... send it to me or Antonio... or Extrude hone (pricey). I suggest this as a must for any buildup. Upper and lower port matching is good if you plan on jumping up in HP in the future. Check out classifieds (ie. Search) for either mine or Antonios. Ask the credability of people on the forum before sending your stuff off, just an FYI.