Head Stud Exceeds Recommended Height

[dennisv]

What to do if the head studs protrude too much? I am finding that the original factory steel studs seem to bottom out with about 138 mm exposed. I am reluctant to force them to the recommended depth to expose 135 mm for fear of damaging the case.

We have a magnesium case for a 1970 914-6 (aka 1969 911T). As suggested in Wayne's book, we had head stud inserts installed. I chased all the threads. To be clear, I'm measuring from flange at the base of the stud. Not the cylinder base. Consistent with the photo in Wayne's book.

[r lane]

Dummy a cylinder and head in place to see if you have plenty of purchase for the 10mm allen wrench. You want all of the threads accounted for in the case as well. Satisfy those 2 things, you are ok. Bob

[Jeff Alton]

Have you chased the threads in the case? Does the case have inserts installed for the headstuds?

Let us know.

Like Bob says above, if the stud is too tall, all you are worried about is making sure the barrel nut can be torqued (allen driver has enough purchase). You will have plenty of thread engagement, the question is, maybe too much?

Cheers

[stownsen914]

You can measure the depth of the female threads, and compare to how deep the stud is going to see if you’re getting full engagement in the case.