ok i have a 97 civic with a 2000 gsr swap... I bought a header online, took the old one out, began to install the new one and noticed it did not fit...what header do i need to purchase for my civic with a diff engine...?

 

you need to buy the header appropriate for that ENGINE, not vehicle if that's what you mean. Also, keep in mind some cheap a$$ companies don't make it so the fitment is perfect.