BIG TUBE HEADERS - 2.25" PRIMARY (Custom Spec)

CMI Big Tube headers enable big block engines with 540 cubic-inch displacements or more to deliver peak horsepower and torque throughout the entire operating range. CMI Big Tube Headers are proven to withstand one of the toughest marine environments on earth – offshore racing – and have powered more National and World Championship boats than all other brands combined. CMI “Big Tubes” can be custom stepped in any configuration to meet any engine builders’ requirements.

The fully polished CMI Big Tube systems are offered with the largest inside diameter options available on the market, including 2 1/8-, two ¼-, and two 3/8-inch inside diameters for any step combination. CMI offers a range of exhaust tailpipe options, as well as CMI's Sound Choice™ selectable silencing system, to complete any installation. All CMI Big Tube systems include stainless steel cooling fluid distribution tubes, header attaching bolts, all necessary gaskets and cooling fittings required for installation. Tailpipes sold separately.