440 Header/Head Mounting Bolt
Anyway, if you decide on a stud and you blow up the Schumacher picture, you can make out they are a combination, course and fine thread. Likely 3/8-16 x 3/8-24 stud. Check NAPA or possibly a Doorman parts rack. If you do use a stud make sure the shank portion between the two threads isn't too long to tighten the header flange adequately. If the nut bottoms into a shank that is too long and the shank is driven into the head, it could cause the cast to split, crack, or strip threads.
Hmmm.........sounds like this issue just may have been chased around previously.
Anyway, if you decide on a stud and you blow up the Schumacher picture, you can make out they are a combination, course and fine thread. Likely 3/8-16 x 3/8-24 stud. Check NAPA or possibly a Doorman parts rack. If you do use a stud make sure the shank portion between the two threads isn't too long to tighten the header flange adequately. If the nut bottoms into a shank that is too long and the shank is driven into the head, it could cause the cast to split, crack, or strip threads.
