Summary It's important to be aware of the difference between exhaust manifold studs and bolts when working on your car. Studs are more robust and won't break as simply as bolts. Bolts can appear loose and cause leaks. For a while now a few makers have available a "stepped header". https://brakerotorresurfacingcora18517.widblog.com/82136359/the-smart-trick-of-types-of-bolts-for-exhaust-that-no-one-is-discussing