Are headers specific for certain heads?

[Scot_94GT]

I am about to buy some BBK longtubes, asd I am wondering if they will work with upgraded heads that I may buy in the future (I have stock heads now). Are the ports and such the same on say an Edelbrock or GT-40 heads as they are on the stock e7's? I ask because there are gt-40 "p" specific headers out there, so I am wondering if if invest ~$400 on headers, will I be able to use them in the future?

Thanks,

 

[mootang]

the bbk long tubes should fit all small block ford heads.

however i had som old short tube headers and one of the tubes rest against the head and i couldn't get it to seal that is why i switched to the long tubes. but the short tubes i had were an old design so i don't know about the new ones.