10x 1.25. to reinstall them try putting two nuts on tight to each other and only turning the outer nut , should tighten the stud into the head plenty.rotorific wrote:Hey guys I was wondering if anyone knew the exhaust manifold stud size. I pulled a couple out when I was replacing my manifold and I have a leak. I would like to try and find some like these from Mugen they have a hex head to install them. http://www.kingmotorsports.com...at=65