brandon_01_ta

well today i replaced my cat-less pacesetter Y with and custon 2.5" Y plus two flowmonster metallic cats plus the flowmaster 2.5 to 3" merge.... and i love the new sound plus the fact the car runs so much better now... it basically eliminated any and all rasp and now has a much more smooth tone, and didnt quieten it down much at all.... and there is ALOT more low and midrange power... it's great...
now, the only problem is that i can hear an exhaust leak so i took it back out to the shop and the guy said the exhaust leak is coming from the headers up on the block and not from under the car... my question is, what is causing this and how hard will it be to fix it? is it maybe i have a bolt loose or bad gaskets??
and do yall think they will charge me a fortune to have that fixed? thanks!