Our k20/k24 turbo manifolds are fabricated from 304 Stainless Steel Sch 10 pipe, all professionally Tig Welded and Backed by Lifetime warranty against cracking. All our manifolds are back purged for the strongest, cleanest welds possible. Each of our manifolds are hand ported to ensure maximum flow, and all surfaces are milled so that there is no room for leakage. These manifold are built to accommodate a gt42 style/series T4 turbo, With the "Lean" engine mounts. Dual 44mm/46mm wastegates flanges will keep your boost under control. . This is the same manifold used on the JJ auto werks SFWD k-series, which has ran a best time of 8.29 @179 MPH!!! We also offer downpipe and dumptubes to go along with these manifolds.