I have a after market fuel rail, dont know the name brand but it has the 6an fitting on both side. I need to get 8an fitting but i cannot find whats the size that goes into the fuel rail. I tired 3/8 lil to big, tried 1/4 to small and 8an is to big to go in and 6an is to small. Here is the picture of the fitting that came with the fuel rail, does anybody know what size that maybe be that will go in the fuel rail? It looks like little bigger then 6an size.

 

looks like a -8an fitting

 

that is 6an to i dont know what size, thats why im trying to find out what that size is.

 

8an is to big, wont fit