nut on left is locknut to make adjustable, appears to be 7/16"?
the nut on the right is a factory Pontiac shoulder nut, 3/8" for factory studs, which is to be torqued down to 20 ft lbs. That is for bone stock factory original valve train. Once you start changing cams etc you need to adjust the lash and the stock nuts have no means to hold other than torqued down tight. So then you use a lock nut or a fancy aftermarket deal with a setscrew.
|