alrite lads can anyone help 
is there much of a performance difference between the standard v4 wrx system and the equalivent sti v4 standard exhaust system? im sure there is just need confirmation, need to know because i have an sti backbox which i was gona marry up to wrx center section but can get the sti center off a fella if i need it, they look both the same but concerned about the flow rate. cheers karl. 
ps i will be using standard wrx cat also.
is there much of a performance difference between the standard v4 wrx system and the equalivent sti v4 standard exhaust system? im sure there is just need confirmation, need to know because i have an sti backbox which i was gona marry up to wrx center section but can get the sti center off a fella if i need it, they look both the same but concerned about the flow rate. cheers karl. ps i will be using standard wrx cat also.