you guys can you tell me what the outlet diameter is on the 4-1 sr headers, i did a search but all i found out was that the 4-2-1 have 2,5" outlet but i didnīt see the 4-1 numbers?
iīm gonna order me some headers in the next couple of weeks so just wanted to be sure

 

They're actually about 2-1/4" at the outlet flange.