Just too give you guys a heads up, I work for Nissan and found that the 03-05 exhaust studs for the exhaust manifold and nuts off a Nissan 350z will work great on a 1jz. They are a tiny bit longer but still works fine with my single. They are the right pitch and are easy to get a hold of.:icon_bigg . Not sure if they will work on the stock twin manifolds though?