...the point I'm making is that the stoc V6 system is made of better quality material than most all aftermarket parts. It was made that way for a reason re: cats, feed gas temps, under hood temps etc. I'd suggest that the data of aftermarket parts materials be compaired to the stoc parts before we all go gung ho on the old BS that aftemarket must always be better than stoc, which, in a lot of cases, is incorrect re: material specs. I further doubt than most aftermarket parts go thru the same durability testing, quality checks etc as the OEM parts have done. Buy what you wish but don't keep kidding yourself that aftermarket is always better.
...even with high grade stainless steels, operations are performed between each stage of working /forming the material. Example, most tubes are supplied pre-annealed. After they are say bent they are annealed again before say hydroforming. This maintains the workability of the material and prevents cracks and splits. Most steels work harden,incl low carbon mild steels. Adding these heat treating steps goes a long way to improve the durability of the final product and we know even welding with localised heat causes the material to become brittle in the area of the weld. This is all basic stuff used when forming and
working materials and is the same now as it was years ago. Many other factors come into play in a fabbed manifold such as 'weld draw', this is the amount of distortion on an assy caused by the heat and the 'order' in which it is welded together. A good company will carry out weld draw testing to establish the 'best order' the welds should be done to say, reduce deformation of flatness on the port flange, again this is all basic engineering practice and has been around for years....Don't get upset, I'm just trying to
improve your know-how....
