I have headman headers that have the oval openings and my engine has 289 heads . what header gaskets do I need oval or rectangle openings ? trying to decide on copper or aluminum gaskets any advice which to use or other options thanks
Doesn't really matter which brand you go with so long as the gasket design has sufficient materiel located above and below the header tube to seal the two..head flange to header port opening.. surfaces together. Most aftermarket aluminum and copper gaskets will allow that matchup but study the pic's to be sure. Some mfgrs will also give port opening dimensions to better match up and compare to the headers port opening too. IOW, doesn't need to match the heads port so much as the headers flange/tube opening itself.
