Are These Head Studs Long Enough?

[philcobill]

This is a photo of a nut on top of a head stud on the aluminum cylinder head I am trying mount on my 1929 Special Coupe's engine block. A gasket is in place and there is a washer under the nut. The stud is hand tightened into the block. The nut was tightened with a regular wrench and not torqued. I imagine that even if it is torqued the nut will not tighten much more. I tried backing off the stud to give more height above the surface of the head. However the studs were loose in the block when backed out to make a difference. My question is what should I do?