Papo J: Here is more info on the manifold, it has been installed since the summer of 2005 and the only problem I had with it was that I didn't install any kind of support for the turbo and the weight and heat cycling cracked the collector in the middle, which was made from a very cheap APC exhaust tip but I was able to weld it and fix it myself. There has been no problems at all with the original welds and the guy who welded the collector and flange for me has 30+ years of welding experience. He said it would work with no issues and so far it has. Oil drain has not been an issue since I chose the correct size hose for the turbo I use but I am planning on removing the manifold and eliminating the collector all together. The manifold works and it is as reliable or more so than the tubular types that are out there. Last year I also modified a stock DMS T25 O2 housing (cast iron) to re-route the down pipe. I cut it to the length I needed and welded the pieces with my flux-core wire welder and so far I have had no issues with it. I guess what I'm trying to say is that you can weld to cast iron, just make sure the surfaces are clean and that you preheat the cast iron pieces and allow them to cool on their own.