Log is fine for all intensive purposes. If you are going huge top mount twins then go tubular. They will crack, engine pull to repair...
hawhawhaw Idjitt! Log manifolds work fine in most cases. However, a decent tubular manifold will outperform a log manifold easily. Crack? Not necessarily!!! Tube type manifold on a Zed with turbos close to stock position is a nightmare!!!! E
About $4000 btw, plenty of better ways to spend $4000 on a Z32, they would have to be price competitive with after market cast log before I would consider, even then the potential issue of cracking etc, the performance gains versus cost and risk just make them unattractive in a Z32. On a full blown race car where the engine is coming in and out and formula restrictions make it necessary to scrap for performance to be competitive, maybe. Obviously for custom installs its easier to make tube then it is to cast metal. http://www.pentroof.co.jp/parts/z32_exm_td.html
