I traced an exhaust leak to a missing nut on one of the studs that connects the precat to the exhaust manifold. Anyone know what the proper size of the nut is so I dont have to do trial and error on a hot exhaust? This is an '86 N/A. Thanks.

 

i believe they are 17mm

 

Thanks for the reply, but I am more interested in the size of the thread. I believe they are M12 but I wanted to be sure.