What is the correct method to install the French Locks used on SB exhaust manifolds?

They go on the outer "horns" of the manifolds, both sides. Between the bolts and the mans. The tabs are folded over onto the bolt heads to keep them from backing out.

I would suggest to wait on folding the tabs over until the engine has gone through a heat cycle or two. After the heat cycle(s), you will want to re-torque the manifold bolts, so wait until after that to fold the tabs over.


dave

Like Dave said, they go only on the outer bolt pairs.
What he didn't say is that the torque spec.s for the outer and inner bolts is different.
Install all the bolts in the manifolds first, then torque the inner bolts to 30~35Ftlbs and then finish torqueing the outer bolt pairs to 15~20Ftlbs and then set (bend over) the french locks to prevent them from loosening.
This is the procedure that was used by GM and will help prevent the manifolds from cracking and breaking between the outer inlet runners.

John