The Quiet Performer! For all popular small block Chevys especially the '55-57s, including the High Output motor, these plain cast headers fit tight to the block, making the QP1000 ideal for any chassis, without a crossmember underneath the motor or behind front mount, using any starter, suspension and steering setup. They provide more steering clearance than any tubular design, even with the Saginaw 605 box. The cast ribs dress up your engine compartment like no other header! Can be used without gaskets. Comes with all hardware necessary for installation.