how is your exhaust hanged ??? here is some thing a lot of people do not know ,headers getting loose and leaky hookups. i do not use street hookup gaskets but the hookup flanges are flat and weld on the headder and the best gaskets to use is the ulra-seal or a graphite type make shure that not to much weight is hanging on the headders and it should move a little with engine if not thing will crack or loosen seim truck band clamps work very good for the street hook ups no flanges or gaskets to blow out.