Don't know about the finer points questioned here (like better overall designs, etc...) but I believe BMW cycles went to Nikasil in the 80's (or early 90's) for several reasons. One was weight, but the primary was heat transfer. It seems a lot is lost in the transfer from the linings to the heads, and this process eliminated this issue. I am sure there are many technical papers, patents, etc., for those who wish to dive deeper. Just not sure I need to go that far, but clearly it is the right technology, and while it may be new here, it is proven stuff!Also, I think rough EXTERIORS on castings increase surface area and help with heat dissipation, so smooth may not be good there. On the inside oil flow must be optimized, thus highly polished interiors are usually desired. Marc Lee Winnig
mlwin...@hotmail.com (815) 301-5011 Cell and Vonage (801) 749-9460 FAX > I have always wondered about the roughness of the castings of the VW jugs and thought the billet stuff would be better but this information far exceeds what I would have expected. It looks like these jugs answer all of the needs, more power, better heat disapation longer TBO and so on. _________________________________________________________________ Get the Live.com Holiday Page for recipes, gift-giving ideas, and more. www.live.com/?addtemplate=holiday