SteelHeader Flange: Small Block Mopar 318 Poly Head, Square Port

Precision laser cut form 3/8" thick mild steel, our header flanges are manufactured in the U.S. and are machine surfaced. These header flanges are specifically made for the stock small block Mopar 318 CID "Poly Head".

Port Size: 1.825" Rect. Port

Preformed Flange Stubs are 2"-3" in length, and are formed to perfectly fit the non-round port in the flange. Stubs drastically reduce overall build time and increase builder's efficiency.

We carry over 250 different header flange designs, so if you don't see the flange you're looking for, talk with one our tech reps about custom header flange cutting.

Flanges sold separately.