Well, I think that the catbacks are suppose to go to the "stock" position of the cat.
So, if you got a header that went to the stock pos of the cat (i.e. hotshot headers or what have you), and a hi-flow cat or watever you wanted that was made to replace the stock one, and then you exhaust, they theoretically should line up ok.
I wouldn't know tho because my hotshots won't come in until may 6th from enjuku racing and I'm still finalizing the orders for my brm exhaust w/ Greg.
I really wanted to get the N1 duals but I'm afraid they're too loud for California popo's

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