Don, tighten the header bolts to the proper torque, then after you run the engine tighten the bolts every day for a week till the header gaskets get seated. torqueing the bolts on a header 1 time will not get the job done. I always check header bolt tightness every month after the gaskets seat. After the gaskets seat purchase the locking header bolts from mike at fspp. If you don't keep on top of header bolt tightness you are just looking for blown header gaskets. :idea: william